initial commit

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

70 files changed, 15847 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
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+*.py[co]
+*~
+*.egg-info/
+build/
+dist/
+
+GTAGS
+GRTAGS
+GPATH
+GSYMS
diff --git a/COPYING b/COPYING
new file mode 100644
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--- /dev/null
+++ b/COPYING
@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
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+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 00000000..e96a659d
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+GPL v3 only
diff --git a/MANIFEST.in b/MANIFEST.in
new file mode 100644
index 00000000..168d8dcd
--- /dev/null
+++ b/MANIFEST.in
@@ -0,0 +1,10 @@
+include COPYING LICENSE
+include README.rst
+include MANIFEST.in
+graft contrib
+graft doc
+graft etc
+recursive-exclude doc/build/*/ *
+global-exclude *~
+global-exclude *.pyc
+global-exclude .gitignore
diff --git a/README.rst b/README.rst
new file mode 100644
index 00000000..44d0c202
--- /dev/null
+++ b/README.rst
@@ -0,0 +1,75 @@
+****************************
+Ryu Network Operating System
+****************************
+
+For details, please see the documentation under doc/ directory and
+make html (or make <format you prefer>). If you have any
+questions, suggestions, and patches, the mailing list is available at
+`ryu-devel ML
+<https://lists.sourceforge.net/lists/listinfo/ryu-devel>`_.
+
+Ryu Official site is `<http://www.osrg.net/ryu/>`_.
+
+
+Overview
+========
+Ryu is an open-sourced Network Operating System (NOS) licensed under
+GPL v3. It's fully written in Python.
+
+Ryu aims to provide a logically centralized control and well defined
+API that make it easy for operators to create new network management
+and control applications. Currently, Ryu supports OpenFlow protocol to
+modify the behavior of network devices.
+
+We aim at the de facto OSS NOS implementation and NOS API.
+
+Currently, Ryu is shipped with one control application for `OpenStack
+<http://openstack.org/.>`_ network management L2 segregation of
+tenants without using VLAN. The application includes changes to
+OpenStack (nova, quantum ovs plugin, etc).
+
+The project goal is to develop an OSS Network Operating System that
+has high quality enough for use in large production environment in
+code quality/functionality/usability.
+
+
+TODO
+====
+* OpenFlow Protocol version 1.2 (right after the spec release)
+* The better API for control applications
+* Cluster support
+* ...too many for here.
+
+
+Quick Start
+===========
+Get source code::
+
+   % git clone git://github.com/osrg/ryu.git
+
+Then just type::
+
+   % cd ryu; python ./setup.py install
+
+and run ryu-manager command which is installed.
+Then set up your openflow switch (hardware switch or OVS) to connect the ip
+address and port to which ryu-manager is listening.
+If you want to use it with Openstack (nova and quantum with ovs plugin),
+please refer detailed documents under doc/ directory.
+
+
+Requirement
+===========
+* python-setuptools
+* python-gevent >= 0.13
+* python-gflags
+* python-sphinx
+
+
+Project Members
+===============
+* OHMURA Kei <ohmura.kei at lab.ntt.co.jp>
+* MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
+* Isaku Yamahata <yamahata at valinux co jp>
+* FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> 
+
diff --git a/bin/ryu-client b/bin/ryu-client
new file mode 100755
index 00000000..e91ed739
--- /dev/null
+++ b/bin/ryu-client
@@ -0,0 +1,55 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import sys
+from optparse import OptionParser
+
+from ryu.app.client import OFPClient
+
+
+def client_test():
+    parser = OptionParser(usage="Usage: %prog [OPTIONS] <command> [args]")
+    parser.add_option("-H", "--host", dest="host", type="string",
+                      default="127.0.0.1", help="ip address rest api service")
+    parser.add_option("-p", "--port", dest="port", type="int", default="8080")
+
+    options, args = parser.parse_args()
+    if len(args) == 0:
+        parser.print_help()
+        sys.exit(1)
+
+    client = OFPClient(options.host + ':' + str(options.port))
+    commands = {
+        'list_nets': lambda a: sys.stdout.write(client.get_networks()),
+        'create_net': lambda a: client.create_network(a[1]),
+        'update_net': lambda a: client.update_network(a[1]),
+        'delete_net': lambda a: client.delete_network(a[1]),
+        'list_ports': lambda a: sys.stdout.write(client.get_ports(a[1])),
+        'create_port': lambda a: client.create_port(a[1], a[2], a[3]),
+        'update_port': lambda a: client.update_port(a[1], a[2], a[3]),
+        'delete_port': lambda a: client.delete_port(a[1], a[2], a[3])
+        }
+
+    # allow '-', instead of '_'
+    commands.update(dict([(k.replace('_', '-'), v)
+                          for (k, v) in commands.items()]))
+
+    cmd = args[0]
+    commands[cmd](args)
+
+if __name__ == "__main__":
+    client_test()
diff --git a/bin/ryu-manager b/bin/ryu-manager
new file mode 100755
index 00000000..e8350fe9
--- /dev/null
+++ b/bin/ryu-manager
@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import gevent
+import gflags
+import logging
+import sys
+
+from gevent import monkey
+monkey.patch_all()
+
+from ryu import log
+log.earlyInitLog(logging.DEBUG)
+
+from ryu import flags
+from ryu import utils
+from ryu.base.app_manager import AppManager
+from ryu.controller import controller
+from ryu.app import wsapi
+from ryu.app import rest
+from ryu.controller import network
+
+
+FLAGS = gflags.FLAGS
+gflags.DEFINE_multistring('app_lists',
+                          ['ryu.app.simple_isolation.SimpleIsolation',
+                           'ryu.app.rest.restapi'],
+                          'application module name to run')
+
+
+def main():
+    utils.find_flagfile()
+    args = FLAGS(sys.argv)
+    log.initLog()
+
+    nw = network.network()
+
+    app_mgr = AppManager()
+    app_mgr.load_apps(FLAGS.app_lists, network=nw)
+
+    services = []
+
+    ctlr = controller.OpenFlowController()
+    thr = gevent.spawn_later(0, ctlr)
+    services.append(thr)
+
+    # NOX webservice API
+    ws = wsapi.wsapi()
+    thr = gevent.spawn_later(0, ws)
+    services.append(thr)
+
+    gevent.joinall(services)
+
+if __name__ == "__main__":
+    main()
diff --git a/doc/Makefile b/doc/Makefile
new file mode 100644
index 00000000..2fe1f88f
--- /dev/null
+++ b/doc/Makefile
@@ -0,0 +1,130 @@
+# Makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line.
+SPHINXOPTS    =
+SPHINXBUILD   = sphinx-build
+PAPER         =
+BUILDDIR      = build
+
+# Internal variables.
+PAPEROPT_a4     = -D latex_paper_size=a4
+PAPEROPT_letter = -D latex_paper_size=letter
+ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source
+
+.PHONY: help clean html dirhtml singlehtml pickle json htmlhelp qthelp devhelp epub latex latexpdf text man changes linkcheck doctest
+
+help:
+	@echo "Please use \`make <target>' where <target> is one of"
+	@echo "  html       to make standalone HTML files"
+	@echo "  dirhtml    to make HTML files named index.html in directories"
+	@echo "  singlehtml to make a single large HTML file"
+	@echo "  pickle     to make pickle files"
+	@echo "  json       to make JSON files"
+	@echo "  htmlhelp   to make HTML files and a HTML help project"
+	@echo "  qthelp     to make HTML files and a qthelp project"
+	@echo "  devhelp    to make HTML files and a Devhelp project"
+	@echo "  epub       to make an epub"
+	@echo "  latex      to make LaTeX files, you can set PAPER=a4 or PAPER=letter"
+	@echo "  latexpdf   to make LaTeX files and run them through pdflatex"
+	@echo "  text       to make text files"
+	@echo "  man        to make manual pages"
+	@echo "  changes    to make an overview of all changed/added/deprecated items"
+	@echo "  linkcheck  to check all external links for integrity"
+	@echo "  doctest    to run all doctests embedded in the documentation (if enabled)"
+
+clean:
+	-rm -rf $(BUILDDIR)/*
+
+html:
+	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html
+	@echo
+	@echo "Build finished. The HTML pages are in $(BUILDDIR)/html."
+
+dirhtml:
+	$(SPHINXBUILD) -b dirhtml $(ALLSPHINXOPTS) $(BUILDDIR)/dirhtml
+	@echo
+	@echo "Build finished. The HTML pages are in $(BUILDDIR)/dirhtml."
+
+singlehtml:
+	$(SPHINXBUILD) -b singlehtml $(ALLSPHINXOPTS) $(BUILDDIR)/singlehtml
+	@echo
+	@echo "Build finished. The HTML page is in $(BUILDDIR)/singlehtml."
+
+pickle:
+	$(SPHINXBUILD) -b pickle $(ALLSPHINXOPTS) $(BUILDDIR)/pickle
+	@echo
+	@echo "Build finished; now you can process the pickle files."
+
+json:
+	$(SPHINXBUILD) -b json $(ALLSPHINXOPTS) $(BUILDDIR)/json
+	@echo
+	@echo "Build finished; now you can process the JSON files."
+
+htmlhelp:
+	$(SPHINXBUILD) -b htmlhelp $(ALLSPHINXOPTS) $(BUILDDIR)/htmlhelp
+	@echo
+	@echo "Build finished; now you can run HTML Help Workshop with the" \
+	      ".hhp project file in $(BUILDDIR)/htmlhelp."
+
+qthelp:
+	$(SPHINXBUILD) -b qthelp $(ALLSPHINXOPTS) $(BUILDDIR)/qthelp
+	@echo
+	@echo "Build finished; now you can run "qcollectiongenerator" with the" \
+	      ".qhcp project file in $(BUILDDIR)/qthelp, like this:"
+	@echo "# qcollectiongenerator $(BUILDDIR)/qthelp/ryu.qhcp"
+	@echo "To view the help file:"
+	@echo "# assistant -collectionFile $(BUILDDIR)/qthelp/ryu.qhc"
+
+devhelp:
+	$(SPHINXBUILD) -b devhelp $(ALLSPHINXOPTS) $(BUILDDIR)/devhelp
+	@echo
+	@echo "Build finished."
+	@echo "To view the help file:"
+	@echo "# mkdir -p $$HOME/.local/share/devhelp/ryu"
+	@echo "# ln -s $(BUILDDIR)/devhelp $$HOME/.local/share/devhelp/ryu"
+	@echo "# devhelp"
+
+epub:
+	$(SPHINXBUILD) -b epub $(ALLSPHINXOPTS) $(BUILDDIR)/epub
+	@echo
+	@echo "Build finished. The epub file is in $(BUILDDIR)/epub."
+
+latex:
+	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
+	@echo
+	@echo "Build finished; the LaTeX files are in $(BUILDDIR)/latex."
+	@echo "Run \`make' in that directory to run these through (pdf)latex" \
+	      "(use \`make latexpdf' here to do that automatically)."
+
+latexpdf:
+	$(SPHINXBUILD) -b latex $(ALLSPHINXOPTS) $(BUILDDIR)/latex
+	@echo "Running LaTeX files through pdflatex..."
+	$(MAKE) -C $(BUILDDIR)/latex all-pdf
+	@echo "pdflatex finished; the PDF files are in $(BUILDDIR)/latex."
+
+text:
+	$(SPHINXBUILD) -b text $(ALLSPHINXOPTS) $(BUILDDIR)/text
+	@echo
+	@echo "Build finished. The text files are in $(BUILDDIR)/text."
+
+man:
+	$(SPHINXBUILD) -b man $(ALLSPHINXOPTS) $(BUILDDIR)/man
+	@echo
+	@echo "Build finished. The manual pages are in $(BUILDDIR)/man."
+
+changes:
+	$(SPHINXBUILD) -b changes $(ALLSPHINXOPTS) $(BUILDDIR)/changes
+	@echo
+	@echo "The overview file is in $(BUILDDIR)/changes."
+
+linkcheck:
+	$(SPHINXBUILD) -b linkcheck $(ALLSPHINXOPTS) $(BUILDDIR)/linkcheck
+	@echo
+	@echo "Link check complete; look for any errors in the above output " \
+	      "or in $(BUILDDIR)/linkcheck/output.txt."
+
+doctest:
+	$(SPHINXBUILD) -b doctest $(ALLSPHINXOPTS) $(BUILDDIR)/doctest
+	@echo "Testing of doctests in the sources finished, look at the " \
+	      "results in $(BUILDDIR)/doctest/output.txt."
diff --git a/doc/source/_static/.placeholder b/doc/source/_static/.placeholder
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/doc/source/_static/.placeholder
diff --git a/doc/source/_templates/.placeholder b/doc/source/_templates/.placeholder
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/doc/source/_templates/.placeholder
diff --git a/doc/source/conf.py b/doc/source/conf.py
new file mode 100644
index 00000000..ed247019
--- /dev/null
+++ b/doc/source/conf.py
@@ -0,0 +1,216 @@
+# -*- coding: utf-8 -*-
+#
+# ryu documentation build configuration file, created by
+# sphinx-quickstart on Mon Dec  5 15:38:48 2011.
+#
+# This file is execfile()d with the current directory set to its containing dir.
+#
+# Note that not all possible configuration values are present in this
+# autogenerated file.
+#
+# All configuration values have a default; values that are commented out
+# serve to show the default.
+
+import sys, os
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#sys.path.insert(0, os.path.abspath('.'))
+
+# -- General configuration -----------------------------------------------------
+
+# If your documentation needs a minimal Sphinx version, state it here.
+#needs_sphinx = '1.0'
+
+# Add any Sphinx extension module names here, as strings. They can be extensions
+# coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
+extensions = []
+
+# Add any paths that contain templates here, relative to this directory.
+templates_path = ['_templates']
+
+# The suffix of source filenames.
+source_suffix = '.rst'
+
+# The encoding of source files.
+#source_encoding = 'utf-8-sig'
+
+# The master toctree document.
+master_doc = 'index'
+
+# General information about the project.
+project = u'ryu'
+copyright = u'2011, ryu development team'
+
+# The version info for the project you're documenting, acts as replacement for
+# |version| and |release|, also used in various other places throughout the
+# built documents.
+#
+# The short X.Y version.
+version = '0.1'
+# The full version, including alpha/beta/rc tags.
+release = '0.1'
+
+# The language for content autogenerated by Sphinx. Refer to documentation
+# for a list of supported languages.
+#language = None
+
+# There are two options for replacing |today|: either, you set today to some
+# non-false value, then it is used:
+#today = ''
+# Else, today_fmt is used as the format for a strftime call.
+#today_fmt = '%B %d, %Y'
+
+# List of patterns, relative to source directory, that match files and
+# directories to ignore when looking for source files.
+exclude_patterns = []
+
+# The reST default role (used for this markup: `text`) to use for all documents.
+#default_role = None
+
+# If true, '()' will be appended to :func: etc. cross-reference text.
+#add_function_parentheses = True
+
+# If true, the current module name will be prepended to all description
+# unit titles (such as .. function::).
+#add_module_names = True
+
+# If true, sectionauthor and moduleauthor directives will be shown in the
+# output. They are ignored by default.
+#show_authors = False
+
+# The name of the Pygments (syntax highlighting) style to use.
+pygments_style = 'sphinx'
+
+# A list of ignored prefixes for module index sorting.
+#modindex_common_prefix = []
+
+
+# -- Options for HTML output ---------------------------------------------------
+
+# The theme to use for HTML and HTML Help pages.  See the documentation for
+# a list of builtin themes.
+html_theme = 'default'
+
+# Theme options are theme-specific and customize the look and feel of a theme
+# further.  For a list of options available for each theme, see the
+# documentation.
+#html_theme_options = {}
+
+# Add any paths that contain custom themes here, relative to this directory.
+#html_theme_path = []
+
+# The name for this set of Sphinx documents.  If None, it defaults to
+# "<project> v<release> documentation".
+#html_title = None
+
+# A shorter title for the navigation bar.  Default is the same as html_title.
+#html_short_title = None
+
+# The name of an image file (relative to this directory) to place at the top
+# of the sidebar.
+#html_logo = None
+
+# The name of an image file (within the static path) to use as favicon of the
+# docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
+# pixels large.
+#html_favicon = None
+
+# Add any paths that contain custom static files (such as style sheets) here,
+# relative to this directory. They are copied after the builtin static files,
+# so a file named "default.css" will overwrite the builtin "default.css".
+html_static_path = ['_static']
+
+# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
+# using the given strftime format.
+#html_last_updated_fmt = '%b %d, %Y'
+
+# If true, SmartyPants will be used to convert quotes and dashes to
+# typographically correct entities.
+#html_use_smartypants = True
+
+# Custom sidebar templates, maps document names to template names.
+#html_sidebars = {}
+
+# Additional templates that should be rendered to pages, maps page names to
+# template names.
+#html_additional_pages = {}
+
+# If false, no module index is generated.
+#html_domain_indices = True
+
+# If false, no index is generated.
+#html_use_index = True
+
+# If true, the index is split into individual pages for each letter.
+#html_split_index = False
+
+# If true, links to the reST sources are added to the pages.
+#html_show_sourcelink = True
+
+# If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
+#html_show_sphinx = True
+
+# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
+#html_show_copyright = True
+
+# If true, an OpenSearch description file will be output, and all pages will
+# contain a <link> tag referring to it.  The value of this option must be the
+# base URL from which the finished HTML is served.
+#html_use_opensearch = ''
+
+# This is the file name suffix for HTML files (e.g. ".xhtml").
+#html_file_suffix = None
+
+# Output file base name for HTML help builder.
+htmlhelp_basename = 'ryudoc'
+
+
+# -- Options for LaTeX output --------------------------------------------------
+
+# The paper size ('letter' or 'a4').
+#latex_paper_size = 'letter'
+
+# The font size ('10pt', '11pt' or '12pt').
+#latex_font_size = '10pt'
+
+# Grouping the document tree into LaTeX files. List of tuples
+# (source start file, target name, title, author, documentclass [howto/manual]).
+latex_documents = [
+  ('index', 'ryu.tex', u'ryu Documentation',
+   u'ryu development team', 'manual'),
+]
+
+# The name of an image file (relative to this directory) to place at the top of
+# the title page.
+#latex_logo = None
+
+# For "manual" documents, if this is true, then toplevel headings are parts,
+# not chapters.
+#latex_use_parts = False
+
+# If true, show page references after internal links.
+#latex_show_pagerefs = False
+
+# If true, show URL addresses after external links.
+#latex_show_urls = False
+
+# Additional stuff for the LaTeX preamble.
+#latex_preamble = ''
+
+# Documents to append as an appendix to all manuals.
+#latex_appendices = []
+
+# If false, no module index is generated.
+#latex_domain_indices = True
+
+
+# -- Options for manual page output --------------------------------------------
+
+# One entry per manual page. List of tuples
+# (source start file, name, description, authors, manual section).
+man_pages = [
+    ('index', 'ryu', u'ryu Documentation',
+     [u'ryu development team'], 1)
+]
diff --git a/doc/source/getting_started.rst b/doc/source/getting_started.rst
new file mode 100644
index 00000000..bfc108ec
--- /dev/null
+++ b/doc/source/getting_started.rst
@@ -0,0 +1,43 @@
+.. _getting_started:
+
+***************
+Getting Started
+***************
+
+Overview/What's Ryu the Network OS
+==================================
+Ryu is an open-sourced Network OS which is licensed under GPL v3.
+It supports openflow protocol.
+
+If you are not familiar with Software Defined Network(SDN) and
+OpenFlow/openflow controller,
+please refer to `openflow org <http://www.openflow.org/>`_ .
+
+The mailing list is available at
+`ryu-devel ML <https://lists.sourceforge.net/lists/listinfo/ryu-devel>`_
+
+
+Installing Ryu Network OS
+=========================
+Extract source code and just type::
+
+   % python ./setup.py install
+
+Then, run ryu-manager.
+It listens to ip address 0.0.0.0 and port 6633 by default.
+Then have your openflow switch (hardware or openvswitch OVS) to connect to
+ryu-manager.
+
+For OVS case, you can done it by
+
+  % ovs-vsctl set-controller <your bridge>  tcp:<ip addr>[:<port: default 6633>]
+
+At the moment, ryu-manager supports only tcp method.
+If you want to use it with openstack nova and quantum OVS plugin,
+Please refer to :ref:`using_with_openstack`.
+
+Configuration
+=============
+It can be configured by passing configuration file like::
+
+  ryu-manager [--flagfile <path to configuration file>]
diff --git a/doc/source/how_l2_segregation_works.rst b/doc/source/how_l2_segregation_works.rst
new file mode 100644
index 00000000..4b0d2b9d
--- /dev/null
+++ b/doc/source/how_l2_segregation_works.rst
@@ -0,0 +1,66 @@
+.. _how_it_works:
+
+****************************
+How Ryu L2 segregation works
+****************************
+This section describes how Ryu L2 segregation works.
+
+tenant/network id creation
+==========================
+When tenant(= network id) is created, Quantum server tells it to Ryu.
+Ryu remembers the network id.
+
+  .. image:: /images/network-creation.png
+
+
+association OVS port to network id
+==================================
+#. When VM instance is created, the network port is created in OVS and
+   it is associated to network id that VM belongs to.
+
+#. quantum OVS agent tells the associated (network id, ovs port) to Ryu.
+   Ryu remembers (network id, ovs port) relationship.
+
+#. quantum OVS agent also tells to Ryu which OVS port is not managed by
+   nova/quantum, but is connected to external ether cable.
+   We call it external OVS port or that the port is external.
+
+
+  .. image:: /images/assoc-ovs-port.png
+
+
+mac learing
+===========
+When VM sends packets, Ryu determins network id from OVS port and then
+associates src mac address to network id.
+
+   .. image:: /images/mac-learning.png
+
+
+packet filtering(L2 unicast case)
+=================================
+* When VM sending L2-unicast packet, Ryu checks if the destination mac
+  address belongs to the same netowrk id of the source mac address which
+  is same to the network id that the OVS port is associated to.
+* If no, the packet is dropped.
+* If yes, send the packet is sent to ports which belongs to the same
+  network id and external port.
+
+   .. image:: /images/filtering-outgoing.png
+   .. image:: /images/filtering-incoming.png
+
+
+packet filtering(L2 broadcast case)
+===================================
+* When VM sending L2-broadcast/multicaset packet, Ryu checks if the source
+  mac address.
+* send the packet to all external ports and all OVS ports that belongs
+  to the same network id of the source mac address.
+* When receiving broacast/multicast packet from the external ports,
+  Ryu checks if the source mac address belongs to known network id.
+
+   * If yes, send the packet to the external ports except incoming one
+     and the all OVS ports that belongs to the network id
+   * if no, drop the packet.
+
+   .. image:: /images/filtering-broadcast.png
diff --git a/doc/source/images/assoc-ovs-port.png b/doc/source/images/assoc-ovs-port.png
new file mode 100644
index 00000000..16e0386a
--- /dev/null
+++ b/doc/source/images/assoc-ovs-port.png
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diff --git a/doc/source/index.rst b/doc/source/index.rst
new file mode 100644
index 00000000..2320e219
--- /dev/null
+++ b/doc/source/index.rst
@@ -0,0 +1,26 @@
+.. ryu documentation master file, created by
+   sphinx-quickstart on Mon Dec  5 15:38:48 2011.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+**********************************
+Welcome to RYU the Network OS(NOS)
+**********************************
+
+Contents:
+
+.. toctree::
+   :maxdepth: 2
+
+   overview.rst
+   getting_started.rst
+   using_with_openstack.rst
+   how_l2_segregation_works.rst
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`
+
diff --git a/doc/source/overview.rst b/doc/source/overview.rst
new file mode 100644
index 00000000..a6210d3d
--- /dev/null
+++ b/doc/source/overview.rst
@@ -0,0 +1 @@
+.. include:: ../../README.rst
diff --git a/doc/source/using_with_openstack.rst b/doc/source/using_with_openstack.rst
new file mode 100644
index 00000000..143a3042
--- /dev/null
+++ b/doc/source/using_with_openstack.rst
@@ -0,0 +1,251 @@
+.. _using_with_openstack:
+
+***************************************************************
+Using Ryu Network OS with with OpenStack as OpenFlow controller
+***************************************************************
+This section describes how to setup openstack (nova, quantum) and
+ryu-manager.
+It is assumed that kvm with libvirt is used and each host machines that run
+nova-compute/nova-network has two physical NICs.
+It would be possible to deploy it with single NIC machines as described at
+the last section.
+
+NOTE: How to use nova isn't described in this document.
+
+Overview
+========
+
+Ryu is designed/implemented with for production use in mind, so it cooperates
+very well with `OpenStack <http://www.openstack.org/>`_ .
+With nova and quantum OVS plugin,
+Ryu provides L2 segregation of Multi-tenants without any switch feature/settings
+like VLAN. So it's very easy to use/experiment/deploy this segregation as 
+the below figure.
+
+    .. image:: /images/logical-view.png
+
+
+
+Physical machine setup
+----------------------
+The following figure depicts how physical hosts are connected and each daemons
+are deployed.
+
+    .. image:: /images/physical-view.png
+
+Although the nova-api, nova-scheduler, nova-network and related openstack
+daemons are installed in each own physical machines in the above picture,
+they can be installed on a physical machine which also runs nova-compute.
+Each host machine has two nics and one is connected to management LAN
+and other is connected to deployment LAN.
+
+
+How to install/setup
+====================
+If you are not familiar with installing/setting up nova/quantum/openvswitch
+from the source, please refer to OpenStack document and get back here again.
+[
+`OpenStack docs <http://docs.openstack.org/>`_ ,
+`Nova <http://www.openstack.org/projects/compute/>`_ ,
+`Quantum <http://docs.openstack.org/incubation/>`_ ,
+`OpenvSwtich and Quantum Part 1 <http://openvswitch.org/openstack/2011/07/25/openstack-quantum-and-open-vswitch-part-1/>`_ ,
+`OpenvSwtich and Quantum Part 2 <http://openvswitch.org/openstack/2011/07/25/openstack-quantum-and-open-vswitch-part-1/>`_ ,
+`OVS Quantum Plugin Documentation <http://openvswitch.org/openstack/documentation/>`_
+]
+
+* Install ryu and run ryu-manager
+   * install ryu from the source code on the hosts on which you run
+       * nova-compute,
+       * quantum-server and
+       * ryu-manager.
+
+     This is because quantum-server and ova quantum agent which runs on
+     nova-compute node needs ryu-client library to communicate ryu-manager.
+
+     Type in ryu source directory::
+
+     % python ./setup.py install
+
+   * edit /etc/ryu/ryu.conf on the host on which you run ryu-manager
+     if necessary
+
+     No configuration is needed on hosts that runs quantum and ovs quantum
+     agent.
+
+   * run ryu network os::
+
+      % ryu-manager [----flagfile /etc/ryu/ryu.conf]
+
+
+* get nova source and quantum source from github
+   * They are a bit modified from openstack master tree. They are available
+     at github for convinience
+
+      * https://github.com/osrg/nova/tree/ryu
+      * https://github.com/osrg/quantum/tree/ryu
+
+     clone them by typing the followings in an appropriate directory::
+
+      % git clone --branch ryu git://github.com/osrg/nova.git
+      % git clone --branch ryu git://github.com/osrg/quantum.git
+
+     If you prefer https, try those::
+
+      % git clone --branch ryu https://github.com/osrg/nova.git
+      % git clone --branch ryu https://github.com/osrg/quantum.git
+
+
+* Install nova and quantum as usual.
+  (And other Openstack related component if necessary. e.g. glance)
+
+  Each daemons can be installed in a single machine or in different machines.
+  Please refer to Openstack documentation for details.
+  You may want to set up multiple nova-compute nodes for interesting use case.
+
+* Setup nova daemons. (Edit nova.conf)
+  Specifically configure nova-network and nova-compute
+
+    * configure nova-network
+       * --fixed_ranges=<setup here>
+       * --network_size=<setup here>
+       * --network_manager=nova.network.quantum.manager.QuantumManage
+       * --quantum_connection_host=<quantume server ip address>
+       * --firewall_driver=nova.virt.libvirt.firewall.NopFirewallDriver
+
+        NOP firewall driver is newly introduced for demonstrating Ryu
+        capability.
+        If you want, other existing firewall driver can be specified.
+        But such specification don't have any effect in fact
+        because ryu directly controls packets to VM instance via OVS bypassing
+        netfilter/iptables.
+
+       * --linuxnet_interface_driver=nova.network.linux_net.LinuxOVSOFInterfaceDriver
+    * set up OVS on each nova-compute node
+
+      If Ubuntu is used, you can install it from packages as
+      openvswitch-datapath-dkms, openvswitch-common, openvswitch-switch
+      If you already use bridge, you may need to edit /etc/modules to load
+      openvswitch kernel module, openvswitch_mod and brcompat_mod,  before
+      bridge module and reboot to unload bridge module.
+
+     And then create ovs bridge::
+  
+     # ovs-vsctl add-br <bridge name: usually br-int>
+
+     And if you connect NIC to OVS bridge.::
+
+     # ovs-vsctl add-port <bridge name:br-int> <ether interface: e.g. eth<N>>
+
+    * configure each nova-compute
+       * --libvirt_type=kvm
+       * --libvirt_ovs_integration_bridge=<OVS bridge:br-int>
+       * --libvirt_vif_type=ethernet
+       * --libvirt_vif_driver=nova.virt.libvirt.vif.LibvirtOpenVswitchDriver
+
+* install quantum server and have quantum to use OVS pluging
+   * Edit [PLUGIN] section of /etc/quantum/plugins.ini
+      * provider = quantum.plugins.openvswitch.ovs_quantum_plugin.OVSQuantumPlugin
+
+   * Edit [OVS] section of
+     /etc/quantum/plugins/openvswitch/ovs_quantum_plugin.ini
+     
+     In addition to normal quantum OVS settings, add the followings.
+      * integration-bridge = <OVS bridge name: br-int>
+      * plugin_driver = quantum.plugins.openvswitch.ovs_quantum_plugin.OFPRyuDriver
+      * agent_driver = OVSQuantumOFPRyuAgent
+      * openflow-controller = <ryu-manager IP address>:<ryu openflow port: default 6633>
+      * openflow-rest-api = <ryu-manager IP address>:<RYU reset API port: default 8080>
+
+   * Run quantum server
+* install quantum OVS agent on each nova-compute node
+   * Edit /etc/quantum/plugins/openvswitch/ovs_quantum_plugin.ini
+   * Run ovs agent::
+
+     # ovs_quantum_agent.py -v ./etc/quantum/plugins/openvswitch/ovs_quantum_plugin.ini
+
+* Then as usual openstack nova operation, create user, project, network and
+  run instances.
+* Enjoy!
+
+
+Testing
+=======
+Yay, now you have ryu network OS set up.
+You would want to really they are L2-segregated.
+
+* create multi projects and run instances.
+* ping/traceroute between them.
+* tcpdump in the instances
+
+The routing between gateway(gw-xxx) of each tenants are disabled
+by nova.network.linux_net.LinuxOVSOFInterfaceDriver by installing iptables
+rule on nova-network host::
+
+  # iptable -t filter -A nova-network-FORWARD --in-interface gw-+ --out-interface gw-+
+
+Thus pinging/tracerouting between VMs in distinct tenants doesn't work.
+If you drop the above rule by::
+
+  # iptable -t filter -D nova-network-FORWARD --in-interface gw-+ --out-interface gw-+
+
+You will see ping/tracerout works. Please notice that the packets go through
+gw-xxx and gw-yyy, not directly.
+
+   .. image:: /images/trace-route.png
+
+
+Caveats
+=======
+* Run the following daemons in this order
+   #. Run Ryu network OS
+   #. Run quantum with OVS plugin
+   #. Run quantum OVS agent
+   #. run your guest instance
+
+   For now, ryu-manager doesn't have persistent store, so if it's rebooted,
+   all the necessary information must be told again from quantum server/agent.
+
+* nova-manage network delete doesn't work
+
+  At this moment, quantum doesn't implement network delete fully yet.
+  If you issue the command, it fails. And you need to fix nova/quantum DB 
+  by hand using SQL.
+
+
+Appendix
+========
+In the above, two physical NIC deployment is described.
+Some people may want to use those settings with single NIC machine or even
+with single machine.
+It would be possible as the following pictures, but we haven't tested those
+setting. If you success it, please report it.
+
+single NIC/All-in-One setting
+-----------------------------
+If your host machines have only single NIC, it would be possible to use
+Ryu network OS with Linux bridge. However we haven't tested such setups.
+
+    .. image:: /images/compute-node.png
+
+
+All-in-One Setup
+----------------
+You can also setup in single physical host as the following picture.
+
+    .. image:: /images/minimul-setup.png
+
+You can setup the above environment quickly using DevStack.
+
+  #. Install Ubuntu 11.10 (Oneiric)
+
+  #. Download Ryu enabled DevStack from github
+     ::
+
+     % git clone --branch ryu git://github.com/osrg/devstack.git
+
+  #. Start the install
+     ::
+
+     % cd devstack; ./stack.sh
+
+     It will take a few minutes.
diff --git a/etc/ryu/ryu.conf b/etc/ryu/ryu.conf
new file mode 100644
index 00000000..604e2609
--- /dev/null
+++ b/etc/ryu/ryu.conf
@@ -0,0 +1,7 @@
+# Sample configuration file 
+
+#--wsapi_host=<hostip>
+#--wsapi_port=<port:8080>
+#--ofp_listen_host=<hostip>
+#--ofp_listen_port=<port:6633>
+#--simple_isolation_allow_host=False
diff --git a/ryu/__init__.py b/ryu/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/ryu/__init__.py
diff --git a/ryu/app/__init__.py b/ryu/app/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/ryu/app/__init__.py
diff --git a/ryu/app/client.py b/ryu/app/client.py
new file mode 100644
index 00000000..1371a06e
--- /dev/null
+++ b/ryu/app/client.py
@@ -0,0 +1,74 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import httplib
+import urlparse
+
+
+class OFPClientV1_0(object):
+    version = 'v1.0'
+
+    # /{network_id}/{dpid}_{port}
+    network_path = '%s'
+    port_path = '%s/%s_%s'
+
+    def __init__(self, address):
+        r = urlparse.SplitResult('', address, '', '', '')
+        self.host = r.hostname
+        self.port = r.port
+        self.url_prefix = '/' + self.version + '/'
+
+    def _do_request(self, method, action):
+        conn = httplib.HTTPConnection(self.host, self.port)
+        url = self.url_prefix + action
+        conn.request(method, url)
+        res = conn.getresponse()
+        if res.status in (httplib.OK,
+                          httplib.CREATED,
+                          httplib.ACCEPTED,
+                          httplib.NO_CONTENT):
+            return res
+
+        raise httplib.HTTPException('code %d reason %s' %
+                                    (res.status, res.reason))
+
+    def get_networks(self):
+        res = self._do_request('GET', '')
+        return res.read()
+
+    def create_network(self, network_id):
+        self._do_request('POST', self.network_path % network_id)
+
+    def update_network(self, network_id):
+        self._do_request('PUT', self.network_path % network_id)
+
+    def delete_network(self, network_id):
+        self._do_request('DELETE', self.network_path % network_id)
+
+    def get_ports(self, network_id):
+        res = self._do_request('GET', self.network_path % network_id)
+        return res.read()
+
+    def create_port(self, network_id, dpid, port):
+        self._do_request('POST', self.port_path % (network_id, dpid, port))
+
+    def update_port(self, network_id, dpid, port):
+        self._do_request('PUT', self.port_path % (network_id, dpid, port))
+
+    def delete_port(self, network_id, dpid, port):
+        self._do_request('DELETE', self.port_path % (network_id, dpid, port))
+
+
+OFPClient = OFPClientV1_0
diff --git a/ryu/app/rest.py b/ryu/app/rest.py
new file mode 100644
index 00000000..2d9a81b3
--- /dev/null
+++ b/ryu/app/rest.py
@@ -0,0 +1,210 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import json
+from ryu.exception import NetworkNotFound, NetworkAlreadyExist
+from ryu.exception import PortNotFound, PortAlreadyExist
+from ryu.app.wsapi import *
+
+# REST API
+
+# get the list of networks
+# GET /v1.0/
+#
+# register a new network.
+# Fail if the network is already registered.
+# POST /v1.0/{network-id}
+#
+# update a new network.
+# Success as nop even if the network is already registered.
+#
+# PUT /v1.0/{network-id}
+#
+# remove a network
+# DELETE /v1.0/{network-id}
+#
+# get the list of sets of dpid and port
+# GET /v1.0/{network-id}/
+#
+# register a new set of dpid and port
+# Fail if the port is already registered.
+# POST /v1.0/{network-id}/{dpid}_{port-id}
+#
+# update a new set of dpid and port
+# Success as nop even if same port already registered
+# PUT /v1.0/{network-id}/{dpid}_{port-id}
+#
+# remove a set of dpid and port
+# DELETE /v1.0/{network-id}/{dpid}_{port-id}
+
+# We store networks and ports like the following:
+#
+# {network_id: [(dpid, port), ...
+# {3: [(3,4), (4,7)], 5: [(3,6)], 1: [(5,6), (4,5), (4, 10)]}
+#
+
+
+class WSPathNetwork(WSPathComponent):
+    """ Match a network id string """
+
+    def __str__(self):
+        return "{network-id}"
+
+    def extract(self, pc, data):
+        if pc == None:
+            return WSPathExtractResult(error="End of requested URI")
+
+        return WSPathExtractResult(value=pc)
+
+
+class WSPathPort(WSPathComponent):
+    """ Match a {dpid}_{port-id} string """
+
+    def __str__(self):
+        return "{dpid}_{port-id}"
+
+    def extract(self, pc, data):
+        if pc == None:
+            return WSPathExtractResult(error="End of requested URI")
+
+        try:
+            dpid_str, port_str = pc.split('_')
+            dpid = int(dpid_str, 16)
+            port = int(port_str)
+        except ValueError:
+            return WSPathExtractResult(error="Invalid format: %s" % pc)
+
+        return WSPathExtractResult(value={'dpid': dpid, 'port': port})
+
+
+class restapi:
+
+    def __init__(self, *args, **kwargs):
+        self.ws = wsapi()
+        self.api = self.ws.get_version("1.0")
+        self.nw = kwargs['network']
+        self.register()
+
+    def list_networks_handler(self, request, data):
+        request.setHeader("Content-Type", 'application/json')
+        return json.dumps(self.nw.list_networks())
+
+    def create_network_handler(self, request, data):
+        network_id = data['{network-id}']
+
+        try:
+            self.nw.create_network(network_id)
+        except NetworkAlreadyExist:
+            request.setResponseCode(409)
+
+        return ""
+
+    def update_network_handler(self, request, data):
+        network_id = data['{network-id}']
+        self.nw.update_network(network_id)
+        return ""
+
+    def remove_network_handler(self, request, data):
+        network_id = data['{network-id}']
+
+        try:
+            self.nw.remove_network(network_id)
+        except NetworkNotFound:
+            request.setResponseCode(404)
+
+        return ""
+
+    def list_ports_handler(self, request, data):
+        network_id = data['{network-id}']
+
+        try:
+            body = json.dumps(self.nw.list_ports(network_id))
+        except NetworkNotFound:
+            body = ""
+            request.setResponseCode(404)
+
+        request.setHeader("Content-Type", 'application/json')
+        return body
+
+    def create_port_handler(self, request, data):
+        network_id = data['{network-id}']
+        dpid = data['{dpid}_{port-id}']['dpid']
+        port = data['{dpid}_{port-id}']['port']
+
+        try:
+            self.nw.create_port(network_id, dpid, port)
+        except NetworkNotFound:
+            request.setResponseCode(404)
+        except PortAlreadyExist:
+            request.setResponseCode(409)
+
+        return ""
+
+    def update_port_handler(self, request, data):
+        network_id = data['{network-id}']
+        dpid = data['{dpid}_{port-id}']['dpid']
+        port = data['{dpid}_{port-id}']['port']
+
+        try:
+            self.nw.update_port(network_id, dpid, port)
+        except NetworkNotFound:
+            request.setResponseCode(404)
+
+        return ""
+
+    def remove_port_handler(self, request, data):
+        network_id = data['{network-id}']
+        dpid = data['{dpid}_{port-id}']['dpid']
+        port = data['{dpid}_{port-id}']['port']
+
+        try:
+            self.nw.remove_port(network_id, dpid, port)
+        except (NetworkNotFound, PortNotFound):
+            request.setResponseCode(404)
+
+        return ""
+
+    def register(self):
+        self.api.register_request(self.list_networks_handler, "GET",
+                                  [],
+                                  "get the list of networks")
+
+        self.api.register_request(self.create_network_handler, "POST",
+                                  [WSPathNetwork()],
+                                  "register a new network")
+
+        self.api.register_request(self.update_network_handler, "PUT",
+                                  [WSPathNetwork()],
+                                  "update a network")
+
+        self.api.register_request(self.remove_network_handler, "DELETE",
+                                  [WSPathNetwork()],
+                                  "remove a network")
+
+        self.api.register_request(self.list_ports_handler, "GET",
+                                  [WSPathNetwork()],
+                                  "get the list of sets of dpid and port")
+
+        self.api.register_request(self.create_port_handler, "POST",
+                                  [WSPathNetwork(), WSPathPort()],
+                                  "register a new set of dpid and port")
+
+        self.api.register_request(self.update_port_handler, "PUT",
+                                  [WSPathNetwork(), WSPathPort()],
+                                  "update a set of dpid and port")
+
+        self.api.register_request(self.remove_port_handler, "DELETE",
+                                  (WSPathNetwork(), WSPathPort()),
+                                  "remove a set of dpid and port")
diff --git a/ryu/app/rest_nw_id.py b/ryu/app/rest_nw_id.py
new file mode 100644
index 00000000..5422c81d
--- /dev/null
+++ b/ryu/app/rest_nw_id.py
@@ -0,0 +1,21 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+NW_ID_EXTERNAL = '__NW_ID_EXTERNAL__'
+NW_ID_UNKNOWN = '__NW_ID_UNKNOWN__'
+
+# PORT_TYPE_VM = 'guestvm'
+# PORT_TYPE_GW = 'gateway'
+# PORT_TYPE_EXTERNAL = 'external'
diff --git a/ryu/app/simple_isolation.py b/ryu/app/simple_isolation.py
new file mode 100644
index 00000000..43e945c1
--- /dev/null
+++ b/ryu/app/simple_isolation.py
@@ -0,0 +1,242 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+import struct
+
+from ryu.app.rest_nw_id import NW_ID_UNKNOWN, NW_ID_EXTERNAL
+from ryu.exception import MacAddressDuplicated
+from ryu.exception import PortUnknown
+from ryu.controller import event
+from ryu.controller import mac_to_network
+from ryu.controller import mac_to_port
+from ryu.controller.handler import main_dispatcher
+from ryu.controller.handler import config_dispatcher
+from ryu.controller.handler import set_ev_cls
+from ryu.lib.mac import haddr_to_str
+
+LOG = logging.getLogger('ryu.app.simple_isolation')
+
+
+class SimpleIsolation(object):
+    def __init__(self, *args, **kwargs):
+        self.nw = kwargs['network']
+        self.mac2port = mac_to_port.MacToPortTable()
+        self.mac2net = mac_to_network.MacToNetwork(self.nw)
+
+    @set_ev_cls(event.EventOFPSwitchFeatures, config_dispatcher)
+    def switch_features_handler(self, ev):
+        self.mac2port.dpid_add(ev.msg.datapath_id)
+        self.nw.add_datapath(ev.msg)
+
+    @set_ev_cls(event.EventOFPBarrierReply)
+    def barrier_reply_handler(ev):
+        LOG.debug('barrier reply ev %s msg %s', ev, ev.msg)
+
+    def _modflow_and_send_packet(self, msg, src, dst, actions):
+        datapath = msg.datapath
+
+        #
+        # install flow and then send packet
+        #
+        wildcards = datapath.ofproto.OFPFW_ALL
+        wildcards &= ~(datapath.ofproto.OFPFW_IN_PORT |
+                       datapath.ofproto.OFPFW_DL_SRC |
+                       datapath.ofproto.OFPFW_DL_DST)
+        match = datapath.ofproto_parser.OFPMatch(wildcards,
+                                                 msg.in_port, src, dst,
+                                                 0, 0, 0, 0, 0, 0, 0, 0, 0)
+
+        datapath.send_flow_mod(
+            match=match, cookie=0, command=datapath.ofproto.OFPFC_ADD,
+            idle_timeout=0, hard_timeout=0, priority=32768,
+            buffer_id=0xffffffff, out_port=datapath.ofproto.OFPP_NONE,
+            flags=datapath.ofproto.OFPFF_SEND_FLOW_REM, actions=actions)
+
+        datapath.send_packet_out(msg.buffer_id, msg.in_port, actions)
+
+    def _forward_to_nw_id(self, msg, src, dst, nw_id, out_port):
+        assert out_port is not None
+        datapath = msg.datapath
+
+        if not self.nw.same_network(datapath.id, nw_id, out_port,
+                                    NW_ID_EXTERNAL):
+            LOG.debug('packet is blocked src %s dst %s '
+                      'from %d to %d on datapath %d',
+                      haddr_to_str(src), haddr_to_str(dst),
+                      msg.in_port, out_port, datapath.id)
+            return
+
+        LOG.debug("learned dpid %s in_port %d out_port %d src %s dst %s",
+                  datapath.id, msg.in_port, out_port,
+                  haddr_to_str(src), haddr_to_str(dst))
+        actions = [datapath.ofproto_parser.OFPActionOutput(out_port)]
+        self._modflow_and_send_packet(msg, src, dst, actions)
+
+    def _flood_to_nw_id(self, msg, src, dst, nw_id):
+        datapath = msg.datapath
+        actions = []
+        LOG.debug("dpid %s in_port %d src %s dst %s ports %s",
+                  datapath.id, msg.in_port,
+                  haddr_to_str(src), haddr_to_str(dst),
+                  self.nw.dpids.get(datapath.id, {}).items())
+        for port_no in self.nw.filter_ports(datapath.id, msg.in_port,
+                                            nw_id, NW_ID_EXTERNAL):
+            LOG.debug("port_no %s", port_no)
+            actions.append(datapath.ofproto_parser.OFPActionOutput(port_no))
+        self._modflow_and_send_packet(msg, src, dst, actions)
+
+    def _learned_mac_or_flood_to_nw_id(self, msg, src, dst,
+                                       dst_nw_id, out_port):
+        if out_port is not None:
+            self._forward_to_nw_id(msg, src, dst, dst_nw_id, out_port)
+        else:
+            self._flood_to_nw_id(msg, src, dst, dst_nw_id)
+
+    @set_ev_cls(event.EventOFPPacketIn, main_dispatcher)
+    def packet_in_handler(self, ev):
+        # LOG.debug('packet in ev %s msg %s', ev, ev.msg)
+        msg = ev.msg
+        datapath = msg.datapath
+
+        dst, src, eth_type = struct.unpack_from('!6s6sH', buffer(msg.data), 0)
+
+        try:
+            port_nw_id = self.nw.get_network(datapath.id, msg.in_port)
+        except PortUnknown:
+            port_nw_id = NW_ID_UNKNOWN
+
+        if port_nw_id != NW_ID_UNKNOWN:
+            # Here it is assumed that the
+            # (port <-> network id)/(mac <-> network id) relationship
+            # is stable once the port is created. The port will be destroyed
+            # before assigning new network id to the given port.
+            # This is correct nova-network/nova-compute.
+            try:
+                # allow external -> known nw id change
+                self.mac2net.add_mac(src, port_nw_id, NW_ID_EXTERNAL)
+            except MacAddressDuplicated:
+                LOG.warn('mac address %s is already in use.'
+                         ' So (dpid %s, port %s) can not use it',
+                         haddr_to_str(src), datapath.id, msg.in_port)
+                #
+                # should we install drop action pro-actively for future?
+                #
+                return
+
+        old_port = self.mac2port.port_add(datapath.id, msg.in_port, src)
+        if old_port is not None and old_port != msg.in_port:
+            # We really overwrite already learned mac address.
+            # So discard already installed stale flow entry which conflicts
+            # new port.
+            wildcards = datapath.ofproto.OFPFW_ALL
+            wildcards &= ~datapath.ofproto.OFPFW_DL_DST
+            match = datapath.ofproto_parser.OFPMatch(wildcards,
+                                                     0, 0, src,
+                                                     0, 0, 0, 0, 0, 0, 0, 0, 0)
+
+            datapath.send_flow_mod(match=match, cookie=0,
+                command=datapath.ofproto.OFPFC_DELETE, idle_timeout=0,
+                hard_timeout=0, priority=32768, out_port=old_port)
+
+            # to make sure the old flow entries are purged.
+            datapath.send_barrier()
+
+        src_nw_id = self.mac2net.get_network(src, NW_ID_UNKNOWN)
+        dst_nw_id = self.mac2net.get_network(dst, NW_ID_UNKNOWN)
+
+        # we handle multicast packet as same as broadcast
+        first_oct = struct.unpack_from('B', dst)[0]
+        broadcast = (dst == '\xff' * 6) or (first_oct & 0x01)
+        out_port = self.mac2port.port_get(datapath.id, dst)
+
+        #
+        # there are several combinations:
+        # in_port: known nw_id, external, unknown nw,
+        # src mac: known nw_id, external, unknown nw,
+        # dst mac: known nw_id, external, unknown nw, and broadcast/multicast
+        # where known nw_id: is quantum network id
+        #       external: means that these ports are connected to outside
+        #       unknown nw: means that we don't know this port is bounded to
+        #                   specific nw_id or external
+        #       broadcast: the destination mac address is broadcast address
+        #                  (or multicast address)
+        #
+        # Can the following logic be refined/shortened?
+        #
+
+        if port_nw_id != NW_ID_EXTERNAL and port_nw_id != NW_ID_UNKNOWN:
+            if broadcast:
+                # flood to all ports of external or src_nw_id
+                self._flood_to_nw_id(msg, src, dst, src_nw_id)
+            elif src_nw_id != NW_ID_EXTERNAL and src_nw_id != NW_ID_UNKNOWN:
+                # try learned mac check if the port is net_id
+                # or
+                # flood to all ports of external or src_nw_id
+                self._learned_mac_or_flood_to_nw_id(msg, src, dst,
+                                                    src_nw_id, out_port)
+            else:
+                # NW_ID_EXTERNAL or NW_ID_UNKNOWN
+                # drop packets
+                return
+
+        elif port_nw_id == NW_ID_EXTERNAL:
+            if src_nw_id != NW_ID_EXTERNAL and src_nw_id != NW_ID_UNKNOWN:
+                if broadcast:
+                    # flood to all ports of external or src_nw_id
+                    self._flood_to_nw_id(msg, src, dst, src_nw_id)
+                elif (dst_nw_id != NW_ID_EXTERNAL and
+                      dst_nw_id != NW_ID_UNKNOWN):
+                    if src_nw_id == dst_nw_id:
+                        # try learned mac
+                        # check if the port is external or same net_id
+                        # or
+                        # flood to all ports of external or src_nw_id
+                        self._learned_mac_or_flood_to_nw_id(msg, src, dst,
+                                                            src_nw_id,
+                                                            out_port)
+                    else:
+                        # should not occur?
+                        LOG.debug("should this case happen?")
+                elif dst_nw_id == NW_ID_EXTERNAL:
+                    # try learned mac
+                    # or
+                    # flood to all ports of external or src_nw_id
+                    self._learned_mac_or_flood_to_nw_id(msg, src, dst,
+                                                        src_nw_id, out_port)
+                else:
+                    assert dst_nw_id == NW_ID_UNKNOWN
+
+            elif src_nw_id == NW_ID_EXTERNAL:
+                # drop packet
+                pass
+            else:
+                # should not occur?
+                # drop packets
+                assert src_nw_id == NW_ID_UNKNOWN
+        else:
+            # drop packets?
+            assert port_nw_id == NW_ID_UNKNOWN
+
+    @set_ev_cls(event.EventOFPPortStatus, main_dispatcher)
+    def port_status_handler(self, ev):
+        msg = ev.msg
+        datapath = msg.datapath
+        datapath.send_delete_all_flows()
+        datapath.send_barrier()
+
+    @set_ev_cls(event.EventOFPBarrierReply, main_dispatcher)
+    def barrier_replay_handler(self, ev):
+        pass
diff --git a/ryu/app/simple_switch.py b/ryu/app/simple_switch.py
new file mode 100644
index 00000000..1a3084ae
--- /dev/null
+++ b/ryu/app/simple_switch.py
@@ -0,0 +1,93 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+import struct
+
+from ryu.controller import event
+from ryu.controller import mac_to_port
+from ryu.controller.handler import main_dispatcher
+from ryu.controller.handler import set_ev_cls
+from ryu.lib.mac import haddr_to_str
+from ryu.lib.mac import haddr_to_bin
+
+
+LOG = logging.getLogger('ryu.app.simple_switch')
+
+# TODO: we should split the handler into two parts, protocol
+# independent and dependant parts.
+
+# TODO: can we use dpkt python library?
+
+# TODO: we need to move the followings to something like db
+
+
+class SimpleSwitch(object):
+    def __init__(self, *args, **kwargs):
+        self.mac2port = mac_to_port.MacToPortTable()
+
+    @set_ev_cls(event.EventOFPPacketIn, main_dispatcher)
+    def packetInHandler(self, ev):
+        msg = ev.msg
+        datapath = msg.datapath
+        ofproto = datapath.ofproto
+
+        dst, src, eth_type = struct.unpack_from('!6s6sH', buffer(msg.data), 0)
+
+        dpid = datapath.id
+        self.mac2port.dpid_add(dpid)
+        LOG.info("packet in %s %s %s %s",
+                 dpid, haddr_to_str(src), haddr_to_str(dst), msg.in_port)
+
+        self.mac2port.port_add(dpid, msg.in_port, src)
+        out_port = self.mac2port.port_get(dpid, dst)
+
+        if out_port == None:
+            LOG.info("out_port not found")
+            out_port = ofproto.OFPP_FLOOD
+
+        actions = [datapath.ofproto_parser.OFPActionOutput(out_port)]
+
+        if out_port != ofproto.OFPP_FLOOD:
+            wildcards = ofproto.OFPFW_ALL
+            wildcards &= ~(ofproto.OFPFW_IN_PORT |
+                           ofproto.OFPFW_DL_DST |
+                           ofproto.OFPFW_NW_TOS)
+            match = datapath.ofproto_parser.OFPMatch(
+                wildcards, msg.in_port,
+                haddr_to_bin('00:00:00:00:00:00'), dst,
+                0, 0, 0, 0, 0, 0, 0, 0, 0)
+
+            datapath.send_flow_mod(
+                match=match, cookie=0, command=ofproto.OFPFC_ADD,
+                idle_timeout=0, hard_timeout=0, priority=32768,
+                flags=ofproto.OFPFF_SEND_FLOW_REM, actions=actions)
+
+        datapath.send_packet_out(msg.buffer_id, msg.in_port, actions)
+
+    @set_ev_cls(event.EventOFPPortStatus, main_dispatcher)
+    def portStatusHandler(self, ev):
+        msg = ev.msg
+        reason = msg.reason
+        port_no = msg.port_no
+
+        ofproto = msg.datapath.ofproto
+        if reason == ofproto.OFPPR_ADD:
+            LOG.info("port added %s", port_no)
+        elif reason == ofproto.OFPPR_DELETE:
+            LOG.info("port deleted %s", port_no)
+        elif reason == ofproto.OFPPR_MODIFY:
+            LOG.info("port modified %s", port_no)
+        else:
+            LOG.info("Illeagal port state %s %s", port_no, reason)
diff --git a/ryu/app/wsapi.py b/ryu/app/wsapi.py
new file mode 100644
index 00000000..6205565a
--- /dev/null
+++ b/ryu/app/wsapi.py
@@ -0,0 +1,578 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# This code is based on webservice.py from NOX project:
+#   Copyright 2008 (C) Nicira, Inc.
+
+import gflags
+import logging
+import re
+import textwrap
+import simplejson
+from copy import copy
+from gevent.pywsgi import WSGIServer
+from webob import Request, Response
+
+LOG = logging.getLogger('ryu.app.wsapi')
+
+FLAGS = gflags.FLAGS
+gflags.DEFINE_string('wsapi_host', '', 'webapp listen host')
+gflags.DEFINE_integer('wsapi_port', 8080, 'webapp listen port')
+
+### Response functions:
+#
+# The following functions can be used to generate various error responses.
+# These should only ever be used for the web-services interface, not the
+# user-facing web interface.
+
+
+def forbidden(request, errmsg, otherInfo={}):
+    """Return an error code indicating client is forbidden from accessing."""
+    request.setResponseCode(403)
+    request.setHeader("Content-Type", "application/json")
+    d = copy(otherInfo)
+    d["displayError"] = errmsg
+    return simplejson.dumps(d)
+
+
+def badRequest(request, errmsg, otherInfo={}):
+    """Return an error indicating a problem in data from the client."""
+    request.setResponseCode(400, "Bad request")
+    request.setHeader("Content-Type", "application/json")
+    d = copy(otherInfo)
+    d["displayError"] = "The server did not understand the request."
+    d["error"] = errmsg
+    return simplejson.dumps(d)
+
+
+def conflictError(request, errmsg, otherURI=None, otherInfo={}):
+    """Return an error indicating something conflicts with the request."""
+    if otherURI != None:
+        request.setResponseCode(409, "Conflicts with another resource")
+        request.setHeader("Location", otherURI.encode("utf-8"))
+    else:
+        request.setResponseCode(409, "Internal server conflict")
+    request.setHeader("Content-Type", "application/json")
+    d = copy(otherInfo)
+    d["displayError"] = "Request failed due to simultaneous access."
+    d["error"] = errmsg
+    d["otherURI"] = otherURI
+    return simplejson.dumps(d)
+
+
+def internalError(request, errmsg, otherInfo={}):
+    """Return an error code indicating an error in the server."""
+    request.setResponseCode(500)
+    request.setHeader("Content-Type", "application/json")
+    d = copy(otherInfo)
+    d["displayError"] = \
+                      "The server failed while attempting to perform request."
+    d["error"] = errmsg
+    return simplejson.dumps(d)
+
+
+def notFound(request, errmsg, otherInfo={}):
+    """Return an error indicating a resource could not be found."""
+    request.setResponseCode(404, "Resource not found")
+    request.setHeader("Content-Type", "application/json")
+    d = copy(otherInfo)
+    d["displayError"] = "The server does not have data for the request."
+    d["error"] = errmsg
+    return simplejson.dumps(d)
+
+
+def methodNotAllowed(request, errmsg, valid_methods, otherInfo={}):
+    """Return an error indicating this request method is not allowed."""
+    request.setResponseCode(405, "Method not allowed")
+    method_txt = ", ".join(valid_methods)
+    request.setHeader("Allow", method_txt)
+    request.setHeader("Content-Type", "application/json")
+    d = copy(otherInfo)
+    d["displayError"] = "The server can not perform this operation."
+    d["error"] = errmsg
+    d["validMethods"] = valid_methods
+    return simplejson.dumps(d)
+
+
+def unauthorized(request, errmsg="", otherInfo={}):
+    """Return an error indicating a client was not authorized."""
+    request.setResponseCode(401, "Unauthorized")
+    request.setHeader("Content-Type", "application/json")
+    if errmsg != "":
+        errmsg = ": " + errmsg
+    d = copy(otherInfo)
+    d["displayError"] = "Unauthorized%s\n\n" % (errmsg, )
+    d["error"] = errmsg
+    d["loginInstructions"] = \
+        "You must login using 'POST /ws.v1/login' nd pass the resulting " + \
+        "cookie with\neach equest."
+    return simplejson.dumps(d)
+
+
+### Message Body handling
+#
+def json_parse_message_body(request):
+    content = request.content.read()
+    content_type = request.getHeader("content-type")
+    if content_type == None or content_type.find("application/json") == -1:
+        e = ["The message body must have Content-Type application/json\n",
+              "instead of %s. " % content_type]
+        if content_type == "application/x-www-form-urlencoded":
+            e.append("The web\nserver decoded the message body as:\n\n")
+            e.append(str(request.args))
+        else:
+            e.append("The message body was:\n\n")
+            e.append(content)
+        LOG.error("".join(e))
+        return None
+    if len(content) == 0:
+        LOG.error("Message body was empty.  "
+                  "It should be valid JSON encoded data for this request.")
+        return None
+    try:
+        data = simplejson.loads(content)
+    except:
+        LOG.error("Message body is not valid json data. "
+                  "It was:\n\n%s" % (content,))
+        return None
+    return data
+
+
+class WhitespaceNormalizer:
+    def __init__(self):
+        self._re = re.compile("\s+")
+
+    def normalize_whitespace(self, s):
+        return self._re.sub(" ", s).strip()
+
+
+class WSPathTreeNode:
+    _wsn = WhitespaceNormalizer()
+
+    def __init__(self, parent, path_component):
+        self.path_component = path_component
+        self._handlers = {}
+        self._parent = parent
+        self._children = []
+        self._tw = textwrap.TextWrapper()
+        self._tw.width = 78
+        self._tw.initial_indent = " " * 4
+        self._tw.subsequent_indent = self._tw.initial_indent
+
+    def parent(self):
+        return self._parent()
+
+    def _matching_child(self, path_component):
+        for c in self._children:
+            if str(c.path_component) == str(path_component):
+                return c
+        return None
+
+    def has_child(self, path_component):
+        return self._matching_child(path_component) != None
+
+    def add_child(self, path_component):
+        c = self._matching_child(path_component)
+        if c == None:
+            c = WSPathTreeNode(self, path_component)
+            self._children.append(c)
+        return c
+
+    def path_str(self):
+        if self._parent == None:
+            return ""
+        return self._parent.path_str() + "/" + str(self.path_component)
+
+    def set_handler(self, request_method, handler, doc):
+        if request_method in self._handlers:
+            raise KeyError("%s %s is already handled by '%s'" %
+                           (request_method, self.path_str(),
+                            repr(self._handlers[request_method][0])))
+        d = self._wsn.normalize_whitespace(doc)
+        d = self._tw.fill(d)
+        self._handlers[request_method] = (handler, d)
+
+    def interface_doc(self, base_path):
+        msg = []
+        p = base_path + self.path_str()
+        for k in self._handlers:
+            msg.extend((k, " ", p, "\n"))
+            doc = self._handlers[k][1]
+            if doc != None:
+                msg.extend((doc, "\n\n"))
+        for c in self._children:
+            msg.append(c.interface_doc(base_path))
+        return "".join(msg)
+
+    def handle(self, t):
+        s = t.next_path_string()
+        if s != None:
+            r = None
+            if len(self._children) == 0:
+                t.request_uri_too_long()
+            for c in self._children:
+                r = c.path_component.extract(s, t.data)
+                if r.error == None:
+                    t.data[str(c.path_component)] = r.value
+                    t.failed_paths = []
+                    r = c.handle(t)
+                    break
+                else:
+                    t.failed_paths.append((c.path_str(), r.error))
+            if len(t.failed_paths) > 0:
+                return t.invalid_request()
+            return r
+        else:
+            try:
+                h, d = self._handlers[t.request_method()]
+            except KeyError:
+                return t.unsupported_method(self._handlers.keys())
+            return t.call_handler(h)
+
+
+class WSPathTraversal:
+
+    def __init__(self, request):
+        self._request = request
+        self._pathiter = iter(request.postpath)
+        self.data = {}
+        self.failed_paths = []
+
+    def request_method(self):
+        return self._request.method
+
+    def next_path_string(self):
+        try:
+            return self._pathiter.next()
+        except StopIteration:
+            return None
+
+    def call_handler(self, handler):
+        try:
+            return handler(self._request, self.data)
+        except Exception, e:
+            LOG.error("caught unhandled exception with path '%s' : %s" % \
+                      (str(self._request.postpath), e))
+            internalError(self._request, "Unhandled server error")
+
+    def _error_wrapper(self, l):
+        msg = []
+        msg.append("You submitted the following request.\n\n")
+        msg.append("    %s %s\n\n" %
+                   (self._request.method, self._request.path))
+        msg.append("This request is not valid. ")
+        msg.extend(l)
+        msg.append("\n\nYou can get a list of all valid requests with the ")
+        msg.append("following request.\n\n    ")
+        msg.append("GET /" + "/".join(self._request.prepath) + "/doc")
+        return "".join(msg)
+
+    def request_uri_too_long(self):
+        e = ["The request URI path extended beyond all available URIs."]
+        return notFound(self._request, self._error_wrapper(e))
+
+    def unsupported_method(self, valid_methods):
+        if len(valid_methods) > 0:
+            e = ["This URI only supports the following methods.\n\n    "]
+            e.append(", ".join(valid_methods))
+        else:
+            e = ["There are no supported request methods\non this URI. "]
+            e.append("It is only used as part of longer URI paths.")
+        return methodNotAllowed(self._request, self._error_wrapper(e),
+                                valid_methods)
+
+    def invalid_request(self):
+        e = []
+        if len(self.failed_paths) > 0:
+            e.append("The following paths were evaluated and failed\n")
+            e.append("for the indicated reason.")
+            for p, m in self.failed_paths:
+                e.append("\n\n    - %s\n      %s" % (p, m))
+        return notFound(self._request, self._error_wrapper(e))
+
+
+### Registering for requests
+#
+class WSRequestHandler:
+    """Class to determine appropriate handler for a web services request."""
+
+    def __init__(self):
+        self._path_tree = WSPathTreeNode(None, None)
+
+    def register(self, handler, request_method, path_components, doc=None):
+        """Register a web services request handler.
+
+        The parameters are:
+
+            - handler: a function to be called when the specified request
+                  method and path component list are matched.  It must
+                  have the signature:
+
+                       handler(request, extracted_data)
+
+                  Here the 'request' parameter is a twisted request object
+                  to be used to output the result and extracted_data is a
+                  dictionary of data extracted by the WSPath subclass
+                  instances in the 'path_components' parameter indexed
+                  by str(path_component_instance).
+
+            - request_method: the HTTP request method of the request to
+                  be handled.
+
+            - path_components: a list of 'WSPathComponent' subclasses
+                  describing the path to be handled.
+
+            - doc: a string describing the result of this request."""
+        pn = self._path_tree
+        for pc in path_components:
+            pn = pn.add_child(pc)
+        pn.set_handler(request_method.upper(), handler, doc)
+
+    def handle(self, request):
+        return self._path_tree.handle(WSPathTraversal(request))
+
+    def interface_doc(self, base_path):
+        """Text describing all current valid requests."""
+        d = """\
+This is a RESTful web interface to NOX network applications.  The applications
+running on this NOX instance support the following requests.\n\n"""
+
+        return d + self._path_tree.interface_doc(base_path)
+
+
+class WSPathExtractResult:
+    def __init__(self, value=None, error=None):
+        self.value = value
+        self.error = error
+
+
+class WSPathComponent:
+    """Base class for WS path component extractors"""
+
+    def __init__(self):
+        """Initialize a path component extractor
+
+        Currently this does nothing but that may change in the future.
+        Subclasses should call this to be sure."""
+        pass
+
+    def __str__(self):
+        """Get the string representation of the path component
+
+        This is used in generating information about the available paths
+        and conform to the following conventions:
+
+            - If a fixed string is being matched, it should be that string.
+            - In all other cases, it should be a description of what is
+              being extracted within angle brackets, for example,
+              '<existing database table name>'.
+
+        This string is also the key in the dictionary callbacks registered
+        with a WSPathParser instance receive to obtain the extracted
+        information."""
+        err = "The '__str__' method must be implemented by subclasses."
+        raise NotImplementedError(err)
+
+    def extract(self, pc, extracted_data):
+        """Determine if 'pc' matches this path component type
+
+        Returns a WSPathExtractResult object with value set to the
+        extracted value for this path component if the extraction succeeded
+        or error set to an error describing why it did not succeed.
+
+        The 'pc' parameter may have the value 'None' if all path components
+        have been exhausted during previous WS path parsing. This is
+        to allow path component types that are optional at the end
+        of a WS.
+
+        The extracted_data parameter contains data extracted
+        from earlier path components, which can be used during the
+        extraction if needed.  It is a dictionary keyed by the
+        str(path_component) for each previous path component."""
+        err = "The 'extract' method must be implemented by subclasses."
+        raise NotImplementedError(err)
+
+
+class WSPathStaticString(WSPathComponent):
+    """Match a static string in the WS path, possibly case insensitive."""
+
+    def __init__(self, str, case_insensitive=False):
+        WSPathComponent.__init__(self)
+        self.case_insensitive = case_insensitive
+        if case_insensitive:
+            self.str = str.lower()
+        else:
+            self.str = str
+
+    def __str__(self):
+        return self.str
+
+    def extract(self, pc, data):
+        if pc == None:
+            return WSPathExtractResult(error="End of requested URI")
+
+        if self.case_insensitive:
+            if pc.lower() == self.str:
+                return WSPathExtractResult(value=pc)
+        else:
+            if pc == self.str:
+                return WSPathExtractResult(value=pc)
+        return WSPathExtractResult(error="'%s' != '%s'" % (pc, self.str))
+
+
+class WSPathRegex(WSPathComponent):
+    """Match a regex in the WS path.
+
+    This can not be used directly but must be subclassed.  Typically
+    the only thing a subclass must override is the '__str__'
+    method.
+
+    The value returned from the 'extract' method is the python regular
+    expression match object, from subgroups in the expression can be
+    examined, etc."""
+    def __init__(self, regexp):
+        WSPathComponent.__init__(self)
+        self.re = re.compile(regexp)
+
+    def extract(self, pc, data):
+        if pc == None:
+            return WSPathExtractResult(error="End of requested URI")
+        m = re.match(pc)
+        if m == None:
+            return WSPathExtractResult(error="Regexp did not match: %s" %
+                                       self.re.pattern)
+        return WSPathExtractResult(value=m)
+
+
+class WSPathTrailingSlash(WSPathComponent):
+    """Match a null string at a location in the WS path.
+
+    This is typically used at the end of a WS path to require a
+    trailing slash."""
+
+    def __init__(self):
+        WSPathComponent.__init__(self)
+
+    def __str__(self):
+        return "/"
+
+    def extract(self, pc, data):
+        if pc == "":
+            return WSPathExtractResult(True)
+        else:
+            return WSPathExtractResult(
+                error="Data following expected trailing slash")
+
+
+# match any string, and retrieve it by 'name'
+# (e.g.,  WSPathArbitraryString('<hostname>')
+class WSPathArbitraryString(WSPathComponent):
+    def __init__(self, name):
+        WSPathComponent.__init__(self)
+        self._name = name
+
+        def __str__(self):
+            return self._name
+
+    def extract(self, pc, data):
+        if pc == None:
+            return WSPathExtractResult(error="End of requested URI")
+        return WSPathExtractResult(unicode(pc, 'utf-8'))
+
+
+class WSRequest:
+
+    def __init__(self, env, start_response):
+        self.env = env
+        self.start_response = start_response
+        self.version = None
+
+        req = Request(env)
+        self.method = req.method
+        self.path = req.path
+        self.segs = [s for s in self.path.split('/') if s]
+
+        self.rsp = Response(status=200)
+
+        try:
+            version_str = self.segs[0]
+        except IndexError:
+            return
+
+        p = re.compile('^v(?P<ver>.+)$')
+        m = p.match(version_str)
+        if m:
+            self.version = m.group('ver')
+
+        self.prepath = [version_str]
+        self.postpath = self.segs[1:]
+
+    def setHeader(self, name, value):
+        self.rsp.headers[name] = value
+
+    def setResponseCode(self, code, message=None):
+        if not isinstance(code, (int, long)):
+            raise TypeError("HTTP response code must be int or long")
+        if message:
+            self.rsp.status = str(code) + " " + message
+        else:
+            self.rsp.status = code
+
+    def sendResponse(self, body):
+        self.rsp.body = body
+        return self.rsp(self.env, self.start_response)
+
+
+class WSRes:
+
+    def _get_interface_doc(self, request, arg):
+        request.setHeader("Content-Type", "text/plain")
+        return self.mgr.interface_doc("/" + "/".join(request.prepath))
+
+    def __init__(self, version='1.0'):
+        self.version = version
+        self.mgr = WSRequestHandler()
+        self.register_request(self._get_interface_doc,
+                              "GET", (WSPathStaticString("doc"),),
+                              """Get a summary of requests supported by this
+                                 web service interface.""")
+
+    def register_request(self, handler, request_method, path_components, doc):
+        self.mgr.register(handler, request_method, path_components, doc)
+
+    def render(self, request):
+        return self.mgr.handle(request)
+
+
+class wsapi:
+
+    _versions = {'1.0': WSRes('1.0')}
+
+    @classmethod
+    def get_version(cls, version):
+        return cls._versions[version]
+
+    def application(self, env, start_response):
+        wsreq = WSRequest(env, start_response)
+        if wsreq.version in wsapi._versions:
+            body = wsapi._versions[wsreq.version].render(wsreq)
+        else:
+            body = notFound(wsreq, "")
+        return wsreq.sendResponse(body)
+
+    def __call__(self):
+        server = WSGIServer((FLAGS.wsapi_host, FLAGS.wsapi_port),
+                            self.application)
+        server.serve_forever()
diff --git a/ryu/base/__init__.py b/ryu/base/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/ryu/base/__init__.py
diff --git a/ryu/base/app_manager.py b/ryu/base/app_manager.py
new file mode 100644
index 00000000..39474e0e
--- /dev/null
+++ b/ryu/base/app_manager.py
@@ -0,0 +1,45 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import itertools
+import logging
+
+from ryu import utils
+from ryu.controller.handler import register_instance
+
+LOG = logging.getLogger('ryu.base.app_manager')
+
+
+class AppManager(object):
+    def __init__(self):
+        self.applications = {}
+
+    def load(self, app_mod_name, *args, **kwargs):
+        # for now, only single instance of a given module
+        # Do we need to support multiple instances?
+        # Yes, maybe for slicing.
+        assert app_mod_name not in self.applications
+
+        cls = utils.import_object(app_mod_name)
+        app = cls(*args, **kwargs)
+        register_instance(app)
+
+        self.applications[app_mod_name] = app
+
+    def load_apps(self, app_lists, *args, **kwargs):
+        for app in itertools.chain.from_iterable([app_list.split(',')
+                                                  for app_list in app_lists]):
+            self.load(app, *args, **kwargs)
+            LOG.info('loading app %s', app)
diff --git a/ryu/controller/__init__.py b/ryu/controller/__init__.py
new file mode 100644
index 00000000..059122a7
--- /dev/null
+++ b/ryu/controller/__init__.py
@@ -0,0 +1,14 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
diff --git a/ryu/controller/controller.py b/ryu/controller/controller.py
new file mode 100644
index 00000000..186f1fc1
--- /dev/null
+++ b/ryu/controller/controller.py
@@ -0,0 +1,201 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import gflags
+import logging
+import gevent
+from gevent.server import StreamServer
+from gevent.queue import Queue
+
+from ryu.ofproto import ofproto
+from ryu.ofproto import ofproto_parser
+from ryu.ofproto import ofproto_v1_0
+from ryu.ofproto import ofproto_v1_0_parser
+
+from ryu.controller import dispatcher
+from ryu.controller import event
+from ryu.controller import handler
+from ryu.lib.mac import haddr_to_bin
+
+LOG = logging.getLogger('ryu.controller.controller')
+
+FLAGS = gflags.FLAGS
+gflags.DEFINE_string('ofp_listen_host', '', 'openflow listen host')
+gflags.DEFINE_integer('ofp_tcp_listen_port', ofproto.OFP_TCP_PORT,
+                      'openflow tcp listen port')
+
+
+class OpenFlowController(object):
+    def __init__(self):
+        super(OpenFlowController, self).__init__()
+
+    # entry point
+    def __call__(self):
+        #LOG.debug('call')
+        self.server_loop()
+
+    def server_loop(self):
+        server = StreamServer((FLAGS.ofp_listen_host,
+                               FLAGS.ofp_tcp_listen_port),
+                              DatapathConnectionFactory)
+        #LOG.debug('loop')
+        server.serve_forever()
+
+
+def _deactivate(method):
+    def deactivate(self):
+        try:
+            method(self)
+        finally:
+            self.is_active = False
+    return deactivate
+
+
+class Datapath(object):
+    supported_ofp_version = {
+        ofproto_v1_0.OFP_VERSION: (ofproto_v1_0,
+                                   ofproto_v1_0_parser),
+        }
+    default_ofp_version = ofproto_v1_0.OFP_VERSION
+
+    def __init__(self, socket, address):
+        super(Datapath, self).__init__()
+
+        self.socket = socket
+        self.address = address
+        self.is_active = True
+
+        # XIX limit queue size somehow to prevent it from eating memory up
+        self.recv_q = Queue()
+        self.send_q = Queue()
+
+        self.ev_q = dispatcher.EventQueue(handler.handshake_dispatcher)
+
+        self.version_sent = None
+        self.version_recv = None
+        self.version_used = None
+        self.set_version(self.default_ofp_version)
+        self.id = None  # datapath_id is unknown yet
+        self.ports = None
+
+    def set_version(self, version):
+        assert version in self.supported_ofp_version
+        self.ofproto, self.ofproto_parser = self.supported_ofp_version[version]
+
+    # Low level socket handling layer
+    @_deactivate
+    def _recv_loop(self):
+        buf = bytearray()
+        required_len = ofproto.OFP_HEADER_SIZE
+
+        while self.is_active:
+            ret = self.socket.recv(ofproto.OFP_MSG_SIZE_MAX)
+            if len(ret) == 0:
+                self.is_active = False
+                break
+            buf += ret
+            while len(buf) >= required_len:
+                (version, msg_type, msg_len, xid) = ofproto_parser.header(buf)
+                required_len = msg_len
+                if len(buf) < required_len:
+                    break
+
+                msg = ofproto_parser.msg(self,
+                                         version, msg_type, msg_len, xid, buf)
+                #LOG.debug('queue msg %s cls %s', msg, msg.__class__)
+                self.recv_q.put(msg)
+
+                buf = buf[required_len:]
+                required_len = ofproto.OFP_HEADER_SIZE
+
+    @_deactivate
+    def _send_loop(self):
+        while self.is_active:
+            buf = self.send_q.get()
+            self.socket.sendall(buf)
+
+    def send(self, buf):
+        self.send_q.put(buf)
+
+    def send_msg(self, msg):
+        assert isinstance(msg, self.ofproto_parser.MsgBase)
+        msg.serialize()
+        # LOG.debug('send_msg %s', msg)
+        self.send(msg.buf)
+
+    def serve(self):
+        send_thr = gevent.spawn(self._send_loop)
+        ev_thr = gevent.spawn(self._event_loop)
+
+        # send hello message immediately
+        self.version_sent = self.ofproto.OFP_VERSION
+        hello = self.ofproto_parser.OFPHello(self)
+        self.send_msg(hello)
+
+        self._recv_loop()
+        gevent.joinall([ev_thr, send_thr])
+
+    @_deactivate
+    def _event_loop(self):
+        while self.is_active:
+            msg = self.recv_q.get()
+            #LOG.debug('_event_loop ev %s cls %s', msg, msg.__class__)
+            self.ev_q.queue(event.ofp_msg_to_ev(msg))
+
+    def send_ev(self, ev):
+        #LOG.debug('send_ev %s', ev)
+        self.ev_q.queue(ev)
+
+    #
+    # Utility methods for convenience
+    #
+    def send_packet_out(self, buffer_id=0xffffffff, in_port=None,
+                        actions=None, data=None):
+        if in_port is None:
+            in_port = self.ofproto.OFPP_NONE
+        packet_out = self.ofproto_parser.OFPPacketOut(
+            self, buffer_id, in_port, actions, data)
+        self.send_msg(packet_out)
+
+    def send_flow_mod(self, match, cookie, command, idle_timeout, hard_timeout,
+                      priority, buffer_id=0xffffffff,
+                      out_port=None, flags=0, actions=None):
+        if out_port is None:
+            out_port = self.ofproto.OFPP_NONE
+        flow_mod = self.ofproto_parser.OFPFlowMod(
+            self, match, cookie, command, idle_timeout, hard_timeout,
+            priority, buffer_id, out_port, flags, actions)
+        self.send_msg(flow_mod)
+
+    def send_delete_all_flows(self):
+        addr = haddr_to_bin('00:00:00:00:00:00')
+        match = self.ofproto_parser.OFPMatch(self.ofproto.OFPFW_ALL,
+                                             0, addr, addr, 0, 0,
+                                             0, 0, 0, 0, 0, 0, 0)
+        self.send_flow_mod(
+            match=match, cookie=0, command=self.ofproto.OFPFC_DELETE,
+            idle_timeout=0, hard_timeout=0, priority=0, buffer_id=0,
+            out_port=self.ofproto.OFPP_NONE, flags=0, actions=None)
+
+    def send_barrier(self):
+        barrier_request = self.ofproto_parser.OFPBarrierRequest(self)
+        self.send_msg(barrier_request)
+
+
+def DatapathConnectionFactory(socket, address):
+    LOG.debug('connected socket:%s address:%s', socket, address)
+
+    datapath = Datapath(socket, address)
+    datapath.serve()
diff --git a/ryu/controller/dispatcher.py b/ryu/controller/dispatcher.py
new file mode 100644
index 00000000..188c41a3
--- /dev/null
+++ b/ryu/controller/dispatcher.py
@@ -0,0 +1,108 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import copy
+import logging
+from gevent import queue
+
+LOG = logging.getLogger('ryu.controller.dispatcher')
+
+
+class EventQueue(object):
+    def __init__(self, dispatcher):
+        self.dispatcher = dispatcher
+        self.is_dispatching = False
+        self.ev_q = queue.Queue()
+
+    def set_dispatcher(self, dispatcher):
+        self.dispatcher = dispatcher
+
+    def queue_raw(self, ev):
+        self.ev_q.put(ev)
+
+    class _EventQueueGuard(object):
+        def __init__(self, ev_q):
+            self.ev_q = ev_q
+
+        def __enter__(self):
+            self.ev_q.is_dispatching = True
+
+        def __exit__(self, type, value, traceback):
+            self.ev_q.is_dispatching = False
+            return False
+
+    def queue(self, ev):
+        if self.is_dispatching:
+            self.queue_raw(ev)
+            return
+
+        with self._EventQueueGuard(self):
+            assert self.ev_q.empty()
+
+            self.dispatcher(ev)
+            while not self.ev_q.empty():
+                ev = self.ev_q.get()
+                self.dispatcher(ev)
+
+
+class EventDispatcher(object):
+    def __init__(self, name):
+        self.name = name
+        self.events = {}
+
+    def register_handler(self, ev_cls, handler):
+        assert callable(handler)
+        self.events.setdefault(ev_cls, [])
+        self.events[ev_cls].append(handler)
+
+    def register_handlers(self, handlers):
+        for ev_cls, h in handlers:
+            self.register_handler(ev_cls, h)
+
+    def unregister_handler(self, ev_cls, handler):
+        del self.events[ev_cls][handler]
+
+    def register_static(self, ev_cls):
+        '''helper decorator to statically register handler for event class'''
+        def register(handler):
+            '''helper decorator to register handler statically '''
+            if isinstance(handler, staticmethod):
+                # class staticmethod is not callable.
+                handler = handler.__func__
+            self.register_handler(ev_cls, handler)
+            return handler
+        return register
+
+    def __call__(self, ev):
+        self.dispatch(ev)
+
+    def dispatch(self, ev):
+        #LOG.debug('dispatch %s', ev)
+        if ev.__class__ not in self.events:
+            LOG.info('unhandled event %s', ev)
+            return
+
+        # Is this necessary?
+        #
+        # copy handler list because the list is not stable.
+        # event handler may block/switch thread execution
+        # and un/register other handlers.
+        #
+        handlers = copy.copy(self.events[ev.__class__])
+
+        for h in handlers:
+            ret = h(ev)
+            if ret is False:
+                break
diff --git a/ryu/controller/event.py b/ryu/controller/event.py
new file mode 100644
index 00000000..54d135d9
--- /dev/null
+++ b/ryu/controller/event.py
@@ -0,0 +1,76 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import inspect
+
+
+class EventBase(object):
+    # Nothing yet
+    pass
+
+
+class EventOFPMsgBase(EventBase):
+    def __init__(self, msg):
+        self.msg = msg
+
+
+#
+# Create event type corresponding to OFP Msg
+#
+
+_OFP_MSG_EVENTS = {}
+
+
+def _ofp_msg_name_to_ev_name(msg_name):
+    return 'Event' + msg_name
+
+
+def ofp_msg_to_ev(msg):
+    name = _ofp_msg_name_to_ev_name(msg.__class__.__name__)
+    return _OFP_MSG_EVENTS[name](msg)
+
+
+def _create_ofp_msg_ev_class(msg_cls):
+    name = _ofp_msg_name_to_ev_name(msg_cls.__name__)
+    # print 'creating event %s' % name
+
+    if name in _OFP_MSG_EVENTS:
+        return
+
+    cls = type(name, (EventOFPMsgBase,),
+               dict(__init__=lambda self, msg:
+                    super(self.__class__, self).__init__(msg)))
+    globals()[name] = cls
+    _OFP_MSG_EVENTS[name] = cls
+
+
+def _create_ofp_msg_ev_from_module(modname):
+    (f, s, t) = modname.rpartition('.')
+    mod = __import__(modname, fromlist=[f])
+    print mod
+    for k, cls in mod.__dict__.items():
+        if not inspect.isclass(cls):
+            continue
+        if 'cls_msg_type' not in cls.__dict__:
+            continue
+        _create_ofp_msg_ev_class(cls)
+
+
+# TODO:XXX
+_PARSER_MODULE_LIST = ['ryu.ofproto.ofproto_v1_0_parser']
+
+for m in _PARSER_MODULE_LIST:
+    # print 'loading module %s' % m
+    _create_ofp_msg_ev_from_module(m)
diff --git a/ryu/controller/handler.py b/ryu/controller/handler.py
new file mode 100644
index 00000000..b60b6fa6
--- /dev/null
+++ b/ryu/controller/handler.py
@@ -0,0 +1,219 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import copy
+import inspect
+import logging
+import struct
+
+from ryu.controller import event
+from ryu.controller import dispatcher
+from ryu.lib.mac import haddr_to_bin
+
+LOG = logging.getLogger('ryu.controller.handler')
+
+handshake_dispatcher = dispatcher.EventDispatcher('handshake')
+config_dispatcher = dispatcher.EventDispatcher('config')
+main_dispatcher = dispatcher.EventDispatcher('main')
+
+
+def set_ev_cls(ev_cls, dispatchers=None):
+    def _set_ev_cls_dec(handler):
+        handler.ev_cls = ev_cls
+        if dispatchers is not None:
+            handler.dispatchers = dispatchers
+        return handler
+    return _set_ev_cls_dec
+
+
+def _is_ev_handler(meth):
+    return 'ev_cls' in meth.__dict__
+
+
+def _listify(may_list):
+    if may_list is None:
+        may_list = []
+    if not isinstance(may_list, list):
+        may_list = [may_list]
+    return may_list
+
+
+def _get_hnd_spec_dispatchers(handler, dispatchers):
+    hnd_spec_dispatchers = _listify(getattr(handler, 'dispatchers', None))
+    # LOG.debug("hnd_spec_dispatchers %s", hnd_spec_dispatchers)
+    if hnd_spec_dispatchers:
+        _dispatchers = copy.copy(dispatchers)
+        _dispatchers.extend(hnd_spec_dispatchers)
+    else:
+        _dispatchers = dispatchers
+
+    return _dispatchers
+
+
+def register_cls(dispatchers=None):
+    dispatchers = _listify(dispatchers)
+
+    def _register_cls_method(cls):
+        for k, f in inspect.getmembers(cls, inspect.isfunction):
+            # LOG.debug('cls %s k %s f %s', cls, k, f)
+            if not _is_ev_handler(f):
+                continue
+
+            _dispatchers = _get_hnd_spec_dispatchers(f, dispatchers)
+            # LOG.debug("_dispatchers %s", _dispatchers)
+            for d in _dispatchers:
+                # LOG.debug('register dispatcher %s ev %s cls %s k %s f %s',
+                #          d.name, f.ev_cls, cls, k, f)
+                d.register_handler(f.ev_cls, f)
+
+    return _register_cls_method
+
+
+def register_instance(i, dispatchers=None):
+    dispatchers = _listify(dispatchers)
+
+    for k, m in inspect.getmembers(i, inspect.ismethod):
+        # LOG.debug('instance %s k %s m %s', i, k, m)
+        if not _is_ev_handler(m):
+            continue
+
+        _dispatchers = _get_hnd_spec_dispatchers(m, dispatchers)
+        # LOG.debug("_dispatchers %s", _dispatchers)
+        for d in _dispatchers:
+            # LOG.debug('register dispatcher %s ev %s k %s m %s',
+            #           d.name, m.ev_cls, k, m)
+            d.register_handler(m.ev_cls, m)
+
+
+@register_cls([handshake_dispatcher, config_dispatcher, main_dispatcher])
+class EchoHandler(object):
+    @staticmethod
+    @set_ev_cls(event.EventOFPEchoRequest)
+    def echo_request_handler(ev):
+        msg = ev.msg
+        # LOG.debug('echo request msg %s %s', msg, str(msg.data))
+        datapath = msg.datapath
+        echo_reply = datapath.ofproto_parser.OFPEchoReply(datapath)
+        echo_reply.data = msg.data
+        datapath.send_msg(echo_reply)
+
+    @staticmethod
+    @set_ev_cls(event.EventOFPEchoReply)
+    def echo_reply_handler(ev):
+        # do nothing
+        # msg = ev.msg
+        # LOG.debug('echo reply ev %s %s', msg, str(msg.data))
+        pass
+
+
+@register_cls([handshake_dispatcher, config_dispatcher, main_dispatcher])
+class ErrorMsgHandler(object):
+    @staticmethod
+    @set_ev_cls(event.EventOFPErrorMsg)
+    def error_msg_handler(ev):
+        msg = ev.msg
+        LOG.debug('error msg ev %s type 0x%x code 0x%x %s',
+                  msg, msg.type, msg.code, str(msg.data))
+        msg.datapath.is_active = False
+
+
+@register_cls(handshake_dispatcher)
+class HandShakeHandler(object):
+    @staticmethod
+    @set_ev_cls(event.EventOFPHello)
+    def hello_handler(ev):
+        LOG.debug('hello ev %s', ev)
+        msg = ev.msg
+        datapath = msg.datapath
+
+        # TODO: check if received version is supported.
+        #       pre 1.0 is not supported
+        if msg.version not in datapath.supported_ofp_version:
+            # send the error
+            error_msg = datapath.ofproto_parser.OFPErrorMsg(datapath)
+            error_msg.type = datapath.ofproto.OFPET_HELLO_FAILED
+            error_msg.code = datapath.ofproto.OFPHFC_INCOMPATIBLE
+            error_msg.data = 'unsupported version 0x%x' % msg.version
+            datapath.send_msg(error_msg)
+            return
+
+        datapath.version = min(datapath.version_sent, msg.version)
+        datapath.set_version(datapath.version)
+
+        # now send feature
+        features_reqeust = datapath.ofproto_parser.OFPFeaturesRequest(datapath)
+        datapath.send_msg(features_reqeust)
+
+        # now move on to config state
+        LOG.debug('move onto config mode')
+        datapath.ev_q.set_dispatcher(config_dispatcher)
+
+
+@register_cls(config_dispatcher)
+class ConfigHandler(object):
+    @staticmethod
+    @set_ev_cls(event.EventOFPSwitchFeatures)
+    def switch_features_handler(ev):
+        msg = ev.msg
+        datapath = msg.datapath
+        LOG.debug('switch features ev %s', msg)
+
+        datapath.id = msg.datapath_id
+        datapath.ports = msg.ports
+
+        ofproto = datapath.ofproto
+        ofproto_parser = datapath.ofproto_parser
+        set_config = ofproto_parser.OFPSetConfig(
+            datapath, ofproto.OFPC_FRAG_NORMAL,
+            128  # TODO:XXX
+            )
+        datapath.send_msg(set_config)
+
+        #
+        # drop all flows in order to put datapath into unknown state
+        #
+        datapath.send_delete_all_flows()
+
+        datapath.send_barrier()
+
+    # The above OFPC_DELETE request may trigger flow removed event.
+    # Just ignore them.
+    @staticmethod
+    @set_ev_cls(event.EventOFPFlowRemoved)
+    def flow_removed_handler(ev):
+        LOG.debug("flow removed ev %s msg %s", ev, ev.msg)
+
+    @staticmethod
+    @set_ev_cls(event.EventOFPBarrierReply)
+    def barrier_reply_handler(ev):
+        LOG.debug('barrier reply ev %s msg %s', ev, ev.msg)
+
+        # move on to main state
+        LOG.debug('move onto main mode')
+        ev.msg.datapath.ev_q.set_dispatcher(main_dispatcher)
+
+
+@register_cls(main_dispatcher)
+class MainHandler(object):
+    @staticmethod
+    @set_ev_cls(event.EventOFPFlowRemoved)
+    def flow_removed_handler(ev):
+        msg = ev.msg
+
+    @staticmethod
+    @set_ev_cls(event.EventOFPPortStatus)
+    def port_status_handler(ev):
+        msg = ev.msg
+        LOG.debug('port status %s', msg.reason)
diff --git a/ryu/controller/mac_to_network.py b/ryu/controller/mac_to_network.py
new file mode 100644
index 00000000..bc189296
--- /dev/null
+++ b/ryu/controller/mac_to_network.py
@@ -0,0 +1,56 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+
+from ryu.exception import MacAddressDuplicated
+from ryu.lib.mac import haddr_to_str
+
+LOG = logging.getLogger('ryu.controller.mac_to_network')
+
+
+class MacToNetwork(object):
+    def __init__(self, nw):
+        self.mac_to_net = {}
+        self.dpid = {}
+        self.nw = nw
+
+    def get_network(self, mac, default=None):
+        return self.mac_to_net.get(mac, default)
+
+    def add_mac(self, mac, nw_id, nw_id_external=None):
+        _nw_id = self.mac_to_net.get(mac)
+        if _nw_id == nw_id:
+            return
+
+        # allow changing from nw_id_external to known nw id
+        if _nw_id is None or _nw_id == nw_id_external:
+            self.mac_to_net[mac] = nw_id
+            LOG.debug('overwrite nw_id: mac %s nw old %s new %s',
+                      haddr_to_str(mac), _nw_id, nw_id)
+            return
+
+        if nw_id == nw_id_external:
+            # this can happens when the packet traverses
+            # VM-> tap-> ovs-> ext-port-> wire-> ext-port-> ovs-> tap-> VM
+            return
+
+        LOG.warn('duplicated nw_id: mac %s nw old %s new %s',
+                 haddr_to_str(mac), _nw_id, nw_id)
+
+        raise MacAddressDuplicated(mac=mac)
+
+    def del_mac(self, mac):
+        del self.mac_to_net[mac]
diff --git a/ryu/controller/mac_to_port.py b/ryu/controller/mac_to_port.py
new file mode 100644
index 00000000..32e61f49
--- /dev/null
+++ b/ryu/controller/mac_to_port.py
@@ -0,0 +1,48 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+from ryu.lib.mac import haddr_to_str
+
+LOG = logging.getLogger('ryu.controller.mac_to_port')
+
+
+class MacToPortTable(object):
+    """MAC addr <-> (dpid, port name)"""
+
+    def __init__(self):
+        self.mac_to_port = {}
+
+    def dpid_add(self, dpid):
+        LOG.debug('dpid_add: 0x%016x', dpid)
+        self.mac_to_port.setdefault(dpid, {})
+
+    def port_add(self, dpid, port, mac):
+        """
+        :returns: old port if learned. (this may be = port)
+                  None otherwise
+        """
+        old_port = self.mac_to_port[dpid].get(mac, None)
+        self.mac_to_port[dpid][mac] = port
+
+        if old_port is not None and old_port != port:
+            LOG.debug('port_add: 0x%016x 0x%04x %s',
+                      dpid, port, haddr_to_str(mac))
+
+        return old_port
+
+    def port_get(self, dpid, mac):
+        # LOG.debug('dpid 0x%016x mac %s', dpid, haddr_to_str(mac))
+        return self.mac_to_port[dpid].get(mac)
diff --git a/ryu/controller/network.py b/ryu/controller/network.py
new file mode 100644
index 00000000..db8c8960
--- /dev/null
+++ b/ryu/controller/network.py
@@ -0,0 +1,155 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+
+from ryu.exception import NetworkNotFound, NetworkAlreadyExist
+from ryu.exception import PortAlreadyExist, PortNotFound, PortUnknown
+from ryu.app.rest_nw_id import NW_ID_UNKNOWN
+
+LOG = logging.getLogger('ryu.controller.network')
+
+
+class network(object):
+    def __init__(self, nw_id_unknown=NW_ID_UNKNOWN):
+        self.nw_id_unknown = nw_id_unknown
+        self.networks = {}
+        self.dpids = {}
+
+    def _check_nw_id_unknown(self, network_id):
+        if network_id == self.nw_id_unknown:
+            raise NetworkAlreadyExist(network_id=network_id)
+
+    def list_networks(self):
+        return self.networks.keys()
+
+    def update_network(self, network_id):
+        self._check_nw_id_unknown(network_id)
+        self.networks.setdefault(network_id, set())
+
+    def create_network(self, network_id):
+        self._check_nw_id_unknown(network_id)
+        if network_id in self.networks:
+            raise NetworkAlreadyExist(network_id=network_id)
+
+        self.networks[network_id] = set()
+
+    def remove_network(self, network_id):
+        try:
+            del(self.networks[network_id])
+        except KeyError:
+            raise NetworkNotFound(network_id=network_id)
+
+    def list_ports(self, network_id):
+        try:
+            # use list() to keep compatibility for output
+            # set() isn't json serializable
+            return list(self.networks[network_id])
+        except KeyError:
+            raise NetworkNotFound(network_id=network_id)
+
+    def _update_port(self, network_id, dpid, port, port_may_exist):
+        def _known_nw_id(nw_id):
+            return nw_id is not None and nw_id != self.nw_id_unknown
+
+        self._check_nw_id_unknown(network_id)
+        try:
+            old_network_id = self.dpids.get(dpid, {}).get(port, None)
+            if ((dpid, port) in self.networks[network_id] or
+                _known_nw_id(old_network_id)):
+                if not port_may_exist:
+                    raise PortAlreadyExist(network_id=network_id,
+                                           dpid=dpid, port=port)
+
+            if old_network_id != network_id:
+                self.networks[network_id].add((dpid, port))
+                if _known_nw_id(old_network_id):
+                    self.networks[old_network_id].remove((dpid, port))
+        except KeyError:
+            raise NetworkNotFound(network_id=network_id)
+
+        self.dpids.setdefault(dpid, {})
+        self.dpids[dpid][port] = network_id
+
+    def create_port(self, network_id, dpid, port):
+        self._update_port(network_id, dpid, port, False)
+
+    def update_port(self, network_id, dpid, port):
+        self._update_port(network_id, dpid, port, True)
+
+    def remove_port(self, network_id, dpid, port):
+        try:
+            self.networks[network_id].remove((dpid, port))
+        except KeyError:
+            raise NetworkNotFound(network_id=network_id)
+        except ValueError:
+            raise PortNotFound(network_id=network_id, dpid=dpid, port=port)
+
+        del self.dpids[dpid][port]
+
+    def same_network(self, dpid, nw_id, out_port, allow_nw_id_external=None):
+        assert nw_id != self.nw_id_unknown
+        dp = self.dpids.get(dpid, {})
+        out_nw = dp.get(out_port)
+
+        if nw_id == out_nw:
+            return True
+
+        if (allow_nw_id_external is not None and
+            (allow_nw_id_external == nw_id or allow_nw_id_external == out_nw)):
+            # allow external network -> known network id
+            return True
+
+        LOG.debug('blocked dpid %s nw_id %s out_port %d out_nw %s'
+                  'external %s',
+                  dpid, nw_id, out_port, out_nw, allow_nw_id_external)
+        return False
+
+    def get_network(self, dpid, port):
+        try:
+            return self.dpids[dpid][port]
+        except KeyError:
+            raise PortUnknown(dpid=dpid, port=port)
+
+    def add_datapath(self, ofp_switch_features):
+        datapath = ofp_switch_features.datapath
+        dpid = ofp_switch_features.datapath_id
+        ports = ofp_switch_features.ports
+        self.dpids.setdefault(dpid, {})
+        dp = self.dpids[dpid]
+        for port_no in ports:
+            if port_no == 0 or port_no >= datapath.ofproto.OFPP_MAX:
+                # skip fake output ports
+                continue
+
+            if port_no not in dp:
+                dp[port_no] = self.nw_id_unknown
+
+    def filter_ports(self, dpid, in_port, nw_id, allow_nw_id_external=None):
+        assert nw_id != self.nw_id_unknown
+        ret = []
+
+        ports = self.dpids.get(dpid, {})
+        for port_no, _nw_id in ports.items():
+            if port_no == in_port:
+                continue
+
+            if _nw_id == nw_id:
+                ret.append(port_no)
+            elif (allow_nw_id_external is not None and
+                  _nw_id == allow_nw_id_external):
+                ret.append(port_no)
+
+        return ret
diff --git a/ryu/exception.py b/ryu/exception.py
new file mode 100644
index 00000000..4ced457d
--- /dev/null
+++ b/ryu/exception.py
@@ -0,0 +1,63 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+class RyuException(Exception):
+    message = 'An unknown exception'
+
+    def __init__(self, msg=None, **kwargs):
+        self.kwargs = kwargs
+        if msg is None:
+            msg = self.message
+
+        try:
+            msg = msg % kwargs
+        except Exception as e:
+            msg = self.message
+
+        super(RyuException, self).__init__(msg)
+
+
+class OFPUnknownVersion(RyuException):
+    message = 'unknown version %(version)x'
+
+
+class OFPMalformedMessage:
+    message = 'malformed message'
+
+
+class NetworkNotFound(RyuException):
+    message = 'no such network id %(network_id)s'
+
+
+class NetworkAlreadyExist(RyuException):
+    message = 'network id %(network_id)s already exists'
+
+
+class PortNotFound(RyuException):
+    message = 'no such port (%(dpid)s, %(port)s) in network %(network_id)s'
+
+
+class PortAlreadyExist(RyuException):
+    message = 'port (%(dpid)s, %(port)s) in network %(network_id)s ' \
+              'already exists'
+
+
+class PortUnknown(RyuException):
+    message = 'unknown network id for port (%(dpid)s %(port)s)'
+
+
+class MacAddressDuplicated(RyuException):
+    message = 'MAC address %(mac)s is duplicated'
diff --git a/ryu/flags.py b/ryu/flags.py
new file mode 100644
index 00000000..c3ad4062
--- /dev/null
+++ b/ryu/flags.py
@@ -0,0 +1,24 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+global flags
+"""
+
+import gflags
+
+FLAGS = gflags.FLAGS
+
+# GLOBAL flags
+gflags.DEFINE_boolean('monkey_patch', False, 'do monkey patch')
diff --git a/ryu/lib/__init__.py b/ryu/lib/__init__.py
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/ryu/lib/__init__.py
diff --git a/ryu/lib/mac.py b/ryu/lib/mac.py
new file mode 100644
index 00000000..2dbf6e80
--- /dev/null
+++ b/ryu/lib/mac.py
@@ -0,0 +1,23 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+def haddr_to_str(addr):
+    return ''.join(['%02x:' % ord(char) for char in addr[0:6]])[:-1]
+
+
+def haddr_to_bin(string):
+    return ''.join(['%c' % chr(int(i, 16)) for i in
+                    string.split(':')])
diff --git a/ryu/log.py b/ryu/log.py
new file mode 100644
index 00000000..4c3159b5
--- /dev/null
+++ b/ryu/log.py
@@ -0,0 +1,82 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import gflags
+import inspect
+import logging
+import os
+import sys
+
+
+FLAGS = gflags.FLAGS
+
+gflags.DEFINE_integer('default_log_level', None, 'default log level')
+gflags.DEFINE_bool('verbose', False, 'show debug output')
+
+gflags.DEFINE_bool('use_stderr', True, 'log to standard error')
+gflags.DEFINE_string('use_syslog', False, 'output to syslog')
+gflags.DEFINE_string('log_dir', None, 'log file directory')
+gflags.DEFINE_string('log_file', None, 'log file name')
+gflags.DEFINE_string('log_file_mode', '0644', 'default log file permission')
+
+
+_early_log_handler = None
+
+
+def earlyInitLog(level=None):
+    global _early_log_handler
+    _early_log_handler = logging.StreamHandler(sys.stderr)
+
+    log = logging.getLogger()
+    log.addHandler(_early_log_handler)
+    if level is not None:
+        log.setLevel(level)
+
+
+def _get_log_file():
+    if FLAGS.log_file:
+        return FLAGS.log_file
+    if FLAGS.log_dir:
+        return os.path.join(FLAGS.logdir,
+                            os.path.basename(inspect.stack()[-1][1])) + '.log'
+    return None
+
+
+def initLog():
+    global _early_log_handler
+
+    log = logging.getLogger()
+    if FLAGS.use_stderr:
+        log.addHandler(logging.StreamHandler(sys.stderr))
+    if _early_log_handler is not None:
+        log.removeHandler(_early_log_handler)
+        _early_log_handler = None
+
+    if FLAGS.use_syslog:
+        syslog = logging.handlers.SysLogHandler(address='/dev/log')
+        log.addHandler(syslog)
+
+    log_file = _get_log_file()
+    if log_file is not None:
+        logging.addHandler(logging.handlers.WatchedFileHandler(log_file))
+        mode = int(FLAGS.log_file_mnode, 8)
+        os.chmod(log_file, mode)
+
+    if FLAGS.verbose:
+        log.setLevel(logging.DEBUG)
+    elif FLAGS.default_log_level is not None:
+        log.setLevel(FLAGS.default_log_level)
+    else:
+        log.setLevel(logging.INFO)
diff --git a/ryu/ofproto/__init__.py b/ryu/ofproto/__init__.py
new file mode 100644
index 00000000..58736d4a
--- /dev/null
+++ b/ryu/ofproto/__init__.py
@@ -0,0 +1,16 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from . import ofproto_v1_0 as ofproto
diff --git a/ryu/ofproto/ofproto_parser.py b/ryu/ofproto/ofproto_parser.py
new file mode 100644
index 00000000..4bc31f87
--- /dev/null
+++ b/ryu/ofproto/ofproto_parser.py
@@ -0,0 +1,49 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import logging
+import struct
+
+from ryu import exception
+
+from . import ofproto
+
+LOG = logging.getLogger('ryu.ofproto.ofproto_parser')
+
+
+def header(buf):
+    assert len(buf) >= ofproto.OFP_HEADER_SIZE
+    #LOG.debug('len %d bufsize %d', len(buf), ofproto.OFP_HEADER_SIZE)
+    return struct.unpack_from(ofproto.OFP_HEADER_PACK_STR, buffer(buf))
+
+
+_MSG_PARSERS = {}
+
+
+def register_msg_parser(version):
+    def register(msg_parser):
+        _MSG_PARSERS[version] = msg_parser
+        return msg_parser
+    return register
+
+
+def msg(datapath, version, msg_type, msg_len, xid, buf):
+    assert len(buf) >= msg_len
+
+    msg_parser = _MSG_PARSERS.get(version)
+    if msg_parser is None:
+        raise exception.OFPUnknownVersion(version=version)
+
+    return msg_parser(datapath, version, msg_type, msg_len, xid, buf)
diff --git a/ryu/ofproto/ofproto_v1_0.py b/ryu/ofproto/ofproto_v1_0.py
new file mode 100644
index 00000000..9ac3b957
--- /dev/null
+++ b/ryu/ofproto/ofproto_v1_0.py
@@ -0,0 +1,437 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from struct import calcsize
+
+# define constants
+OFP_VERSION = 0x01
+OFP_MAX_TABLE_NAME_LEN = 32
+OFP_MAX_TABLE_NAME_LEN_STR = str(OFP_MAX_TABLE_NAME_LEN)
+OFP_MAX_PORT_NAME_LEN = 16
+OFP_TCP_PORT = 6633
+OFP_SSL_PORT = 6633
+OFP_ETH_ALEN = 6
+OFP_ETH_ALEN_STR = str(OFP_ETH_ALEN)
+
+# enum ofp_port
+OFPP_MAX = 0xff00
+OFPP_IN_PORT = 0xfff8	# Send the packet out the input port. This
+                        # virtual port must be explicitly used
+                        # in order to send back out of the input
+                        # port.
+OFPP_TABLE = 0xfff9	# Perform actions in flow table.
+                        # NB: This can only be the destination
+                        # port for packet-out messages.
+OFPP_NORMAL = 0xfffa	# Process with normal L2/L3 switching.
+OFPP_FLOOD = 0xfffb	# All physical ports except input port and
+                        # those disabled by STP.
+OFPP_ALL = 0xfffc	# All physical ports except input port.
+OFPP_CONTROLLER = 0xfffd	# Send to controller.
+OFPP_LOCAL = 0xfffe	# Local openflow "port".
+OFPP_NONE = 0xffff	# Not associated with a physical port.
+
+# enum ofp_type
+OFPT_HELLO = 0	# Symmetric message
+OFPT_ERROR = 1	# Symmetric message
+OFPT_ECHO_REQUEST = 2	# Symmetric message
+OFPT_ECHO_REPLY = 3	# Symmetric message
+OFPT_VENDOR = 4	# Symmetric message
+OFPT_FEATURES_REQUEST = 5	# Controller/switch message
+OFPT_FEATURES_REPLY = 6	# Controller/switch message
+OFPT_GET_CONFIG_REQUEST = 7	# Controller/switch message
+OFPT_GET_CONFIG_REPLY = 8	# Controller/switch message
+OFPT_SET_CONFIG = 9	# Controller/switch message
+OFPT_PACKET_IN = 10	# Async message
+OFPT_FLOW_REMOVED = 11	# Async message
+OFPT_PORT_STATUS = 12	# Async message
+OFPT_PACKET_OUT = 13	# Controller/switch message
+OFPT_FLOW_MOD = 14	# Controller/switch message
+OFPT_PORT_MOD = 15	# Controller/switch message
+OFPT_STATS_REQUEST = 16	# Controller/switch message
+OFPT_STATS_REPLY = 17	# Controller/switch message
+OFPT_BARRIER_REQUEST = 18	# Controller/switch message
+OFPT_BARRIER_REPLY = 19	# Controller/switch message
+OFPT_QUEUE_GET_CONFIG_REQUEST = 20	# Controller/switch message
+OFPT_QUEUE_GET_CONFIG_REPLY = 21	# Controller/switch message
+
+OFP_HEADER_PACK_STR = '!BBHI'
+OFP_HEADER_SIZE = 8
+OFP_MSG_SIZE_MAX = 65535
+assert calcsize(OFP_HEADER_PACK_STR) == OFP_HEADER_SIZE
+
+# define constants
+OFP_DEFAULT_MISS_SEND_LEN = 128
+
+# enum ofp_config_flags
+OFPC_FRAG_NORMAL = 0	# No special handling for fragments.
+OFPC_FRAG_DROP = 1	# Drop fragments.
+OFPC_FRAG_REASM = 2	# Reassemble (only if OFPC_IP_REASM set).
+OFPC_FRAG_NX_MATCH = 3	# Make first fragments available for matching.
+OFPC_FRAG_MASK = 3
+
+OFP_SWITCH_CONFIG_PACK_STR = '!HH'
+OFP_SWITCH_CONFIG_SIZE = 12
+assert (calcsize(OFP_SWITCH_CONFIG_PACK_STR) + OFP_HEADER_SIZE ==
+        OFP_SWITCH_CONFIG_SIZE)
+
+# enum ofp_capabilities
+OFPC_FLOW_STATS = 1 << 0	# Flow statistics.
+OFPC_TABLE_STATS = 1 << 1	# Table statistics.
+OFPC_PORT_STATS = 1 << 2	# Port statistics.
+OFPC_STP = 1 << 3	# 802.1d spanning tree.
+OFPC_RESERVED = 1 << 4	# Reserved, must not be set.
+OFPC_IP_REASM = 1 << 5	# Can reassemble IP fragments.
+OFPC_QUEUE_STATS = 1 << 6	# Queue statistics.
+OFPC_ARP_MATCH_IP = 1 << 7	# Match IP addresses in ARP pkts.
+
+# enum ofp_port_config
+OFPPC_PORT_DOWN = 1 << 0	# Port is administratively down.
+OFPPC_NO_STP = 1 << 1	# Disable 802.1D spanning tree on port.
+OFPPC_NO_RECV = 1 << 2	# Drop all packets except 802.1D
+                        # spanning tree packets
+OFPPC_NO_RECV_STP = 1 << 3	# Drop received 802.1D STP packets.
+OFPPC_NO_FLOOD = 1 << 4	# Do not include this port when flooding.
+OFPPC_NO_FWD = 1 << 5	# Drop packets forwarded to port.
+OFPPC_NO_PACKET_IN = 1 << 6	# Do not send packet-in msgs for port.
+
+# enum ofp_port_state
+OFPPS_LINK_DOWN = 1 << 0	# No physical link present.
+OFPPS_STP_LISTEN = 0 << 8	# Not learning or relaying frames.
+OFPPS_STP_LEARN = 1 << 8	# Learning but not relaying frames.
+OFPPS_STP_FORWARD = 2 << 8	# Learning and relaying frames.
+OFPPS_STP_BLOCK = 3 << 8	# Not part of spanning tree.
+OFPPS_STP_MASK = 3 << 8	# Bit mask for OFPPS_STP_* values.
+
+# enum ofp_port_features
+OFPPF_10MB_HD = 1 << 0	# 10 Mb half-duplex rate support.
+OFPPF_10MB_FD = 1 << 1	# 10 Mb full-duplex rate support.
+OFPPF_100MB_HD = 1 << 2	# 100 Mb half-duplex rate support.
+OFPPF_100MB_FD = 1 << 3	# 100 Mb full-duplex rate support.
+OFPPF_1GB_HD = 1 << 4	# 1 Gb half-duplex rate support.
+OFPPF_1GB_FD = 1 << 5	# 1 Gb full-duplex rate support.
+OFPPF_10GB_FD = 1 << 6	# 10 Gb full-duplex rate support.
+OFPPF_COPPER = 1 << 7	# Copper medium.
+OFPPF_FIBER = 1 << 8	# Fiber medium.
+OFPPF_AUTONEG = 1 << 9	# Auto-negotiation.
+OFPPF_PAUSE = 1 << 10	# Pause.
+OFPPF_PAUSE_ASYM = 1 << 11	# Asymmetric pause.
+
+_OFP_PHY_PORT_PACK_STR = 'H' + OFP_ETH_ALEN_STR + 's' + str(OFP_MAX_PORT_NAME_LEN) + 'sIIIIII'
+OFP_PHY_PORT_PACK_STR = '!' + _OFP_PHY_PORT_PACK_STR
+OFP_PHY_PORT_SIZE  = 48
+assert calcsize(OFP_PHY_PORT_PACK_STR) == OFP_PHY_PORT_SIZE
+
+OFP_SWITCH_FEATURES_PACK_STR = '!QIB3xII'
+OFP_SWITCH_FEATURES_SIZE = 32
+assert (calcsize(OFP_SWITCH_FEATURES_PACK_STR) + OFP_HEADER_SIZE ==
+        OFP_SWITCH_FEATURES_SIZE)
+
+# enum ofp_port_reason
+OFPPR_ADD = 0	# The port was added.
+OFPPR_DELETE = 1	# The port was removed.
+OFPPR_MODIFY = 2	# Some attribute of the port has changed.
+
+OFP_PORT_STATUS_PACK_STR = '!B7x' + _OFP_PHY_PORT_PACK_STR
+OFP_PORT_STATUS_DESC_OFFSET = OFP_HEADER_SIZE + 8
+OFP_PORT_STATUS_SIZE = 64
+assert (calcsize(OFP_PORT_STATUS_PACK_STR) + OFP_HEADER_SIZE ==
+        OFP_PORT_STATUS_SIZE)
+
+OFP_PORT_MOD_PACK_STR = '!H' + OFP_ETH_ALEN_STR + 'BIII4x'
+OFP_PORT_MOD_SIZE = 32
+assert calcsize(OFP_PORT_MOD_PACK_STR) + OFP_HEADER_SIZE == OFP_PORT_MOD_SIZE
+
+# enum ofp_packet_in_reason
+OFPR_NO_MATCH = 0	# No matching flow.
+OFPR_ACTION = 1	# Action explicitly output to controller.
+
+OFP_PACKET_IN_PACK_STR = '!IHHBx2x' # the last 2x is for ofp_packet_in::data
+OFP_PACKET_IN_SIZE = 20
+OFP_PACKET_IN_DATA_OFFSET = 18
+assert calcsize(OFP_PACKET_IN_PACK_STR) + OFP_HEADER_SIZE == OFP_PACKET_IN_SIZE
+
+# enum ofp_action_type
+OFPAT_OUTPUT = 0	# Output to switch port.
+OFPAT_SET_VLAN_VID = 1	# Set the 802.1q VLAN id.
+OFPAT_SET_VLAN_PCP = 2	# Set the 802.1q priority.
+OFPAT_STRIP_VLAN = 3	# Strip the 802.1q header.
+OFPAT_SET_DL_SRC = 4	# Ethernet source address.
+OFPAT_SET_DL_DST = 5	# Ethernet destination address.
+OFPAT_SET_NW_SRC = 6	# IP source address.
+OFPAT_SET_NW_DST = 7	# IP destination address.
+OFPAT_SET_NW_TOS = 8	# IP ToS (DSCP field, 6 bits).
+OFPAT_SET_TP_SRC = 9	# TCP/UDP source port.
+OFPAT_SET_TP_DST = 10	# TCP/UDP destination port.
+OFPAT_ENQUEUE = 11	# Output to queue.
+OFPAT_VENDOR = 0xffff
+
+OFP_ACTION_OUTPUT_PACK_STR = '!HHHH'
+OFP_ACTION_OUTPUT_SIZE = 8
+assert calcsize(OFP_ACTION_OUTPUT_PACK_STR) == OFP_ACTION_OUTPUT_SIZE
+OFP_ACTION_OUTPUT_LEN = 8
+
+# define constants
+OFP_VLAN_NONE = 0xffff
+
+OFP_ACTION_VLAN_VID_PACK_STR = '!HHH2x'
+OFP_ACTION_VLAN_VID_SIZE = 8
+assert calcsize(OFP_ACTION_VLAN_VID_PACK_STR) == OFP_ACTION_VLAN_VID_SIZE
+
+OFP_ACTION_VLAN_PCP_PACK_STR = '!HHB3x'
+OFP_ACTION_VLAN_PCP_SIZE = 8
+assert calcsize(OFP_ACTION_VLAN_PCP_PACK_STR) == OFP_ACTION_VLAN_PCP_SIZE
+
+OFP_ACTION_DL_ADDR_PACK_STR = '!HH' + OFP_ETH_ALEN_STR + 'B6x'
+OFP_ACTION_DL_ADDR_SIZE = 16
+assert calcsize(OFP_ACTION_DL_ADDR_PACK_STR) == OFP_ACTION_DL_ADDR_SIZE
+
+OFP_ACTION_NW_ADDR_PACK_STR = '!HHI'
+OFP_ACTION_NW_ADDR_SIZE = 8
+assert calcsize(OFP_ACTION_NW_ADDR_PACK_STR) == OFP_ACTION_NW_ADDR_SIZE
+
+OFP_ACTION_NW_TOS_PACK_STR = '!HHB3x'
+OFP_ACTION_NW_TOS_SIZE = 8
+assert calcsize(OFP_ACTION_NW_TOS_PACK_STR) == OFP_ACTION_NW_TOS_SIZE
+
+OFP_ACTION_TP_PORT_PACK_STR = '!HHH2x'
+OFP_ACTION_TP_PORT_SIZE = 8
+assert calcsize(OFP_ACTION_TP_PORT_PACK_STR) == OFP_ACTION_TP_PORT_SIZE
+
+OFP_ACTION_VENDOR_HEADER_PACK_STR = '!HHI'
+OFP_ACTION_VENDOR_HEADER_SIZE = 8
+assert (calcsize(OFP_ACTION_VENDOR_HEADER_PACK_STR) ==
+        OFP_ACTION_VENDOR_HEADER_SIZE)
+
+OFP_ACTION_HEADER_PACK_STR = '!HH4x'
+OFP_ACTION_HEADER_SIZE = 8
+assert calcsize(OFP_ACTION_HEADER_PACK_STR) == OFP_ACTION_HEADER_SIZE
+
+OFP_ACTION_QUEUE_PACK_STR = '!HHH6xI'
+OFP_ACTION_QUEUE_SIZE = 16
+assert calcsize(OFP_ACTION_QUEUE_PACK_STR) == OFP_ACTION_QUEUE_SIZE
+
+OFP_ACTION_PACK_STR = '!H'
+# because of union ofp_action
+# OFP_ACTION_SIZE = 8
+# assert calcsize(OFP_ACTION_PACK_STR) == OFP_ACTION_SIZE
+
+OFP_PACKET_OUT_PACK_STR = '!IHH'
+OFP_PACKET_OUT_SIZE = 16
+assert (calcsize(OFP_PACKET_OUT_PACK_STR) + OFP_HEADER_SIZE ==
+        OFP_PACKET_OUT_SIZE)
+
+# enum ofp_flow_mod_command
+OFPFC_ADD = 0	# New flow.
+OFPFC_MODIFY = 1	# Modify all matching flows.
+OFPFC_MODIFY_STRICT = 2	# Modify entry strictly matching wildcards
+OFPFC_DELETE = 3	# Delete all matching flows.
+OFPFC_DELETE_STRICT = 4	# Strictly match wildcards and priority.
+
+# enum ofp_flow_wildcards
+OFPFW_IN_PORT = 1 << 0	# Switch input port.
+OFPFW_DL_VLAN = 1 << 1	# VLAN vid.
+OFPFW_DL_SRC = 1 << 2	# Ethernet source address.
+OFPFW_DL_DST = 1 << 3	# Ethernet destination address.
+OFPFW_DL_TYPE = 1 << 4	# Ethernet frame type.
+OFPFW_NW_PROTO = 1 << 5	# IP protocol.
+OFPFW_TP_SRC = 1 << 6	# TCP/UDP source port.
+OFPFW_TP_DST = 1 << 7	# TCP/UDP destination port.
+OFPFW_NW_SRC_SHIFT = 8
+OFPFW_NW_SRC_BITS = 6
+OFPFW_NW_SRC_MASK = ((1 << OFPFW_NW_SRC_BITS) - 1) << OFPFW_NW_SRC_SHIFT
+OFPFW_NW_SRC_ALL = 32 << OFPFW_NW_SRC_SHIFT
+OFPFW_NW_DST_SHIFT = 14
+OFPFW_NW_DST_BITS = 6
+OFPFW_NW_DST_MASK = ((1 << OFPFW_NW_DST_BITS) - 1) << OFPFW_NW_DST_SHIFT
+OFPFW_NW_DST_ALL = 32 << OFPFW_NW_DST_SHIFT
+OFPFW_DL_VLAN_PCP = 1 << 20	# VLAN priority.
+OFPFW_NW_TOS = 1 << 21	# IP ToS (DSCP field, 6 bits).
+OFPFW_ALL = ((1 << 22) - 1)
+
+# define constants
+OFPFW_ICMP_TYPE = OFPFW_TP_SRC
+OFPFW_ICMP_CODE = OFPFW_TP_DST
+OFP_DL_TYPE_ETH2_CUTOFF = 0x0600
+OFP_DL_TYPE_NOT_ETH_TYPE = 0x05ff
+OFP_VLAN_NONE = 0xffff
+
+_OFP_MATCH_PACK_STR = 'IH' + OFP_ETH_ALEN_STR + 's' + OFP_ETH_ALEN_STR + 'sHBxHBB2xIIHH'
+OFP_MATCH_PACK_STR = '!' + _OFP_MATCH_PACK_STR
+OFP_MATCH_SIZE = 40
+assert calcsize(OFP_MATCH_PACK_STR) == OFP_MATCH_SIZE
+
+OFP_FLOW_PERMANENT = 0
+OFP_DEFAULT_PRIORITY = 0x8000
+
+# enum ofp_flow_mod_flags
+OFPFF_SEND_FLOW_REM = 1 << 0	# Send flow removed message when flow
+                                # expires or is deleted.
+OFPFF_CHECK_OVERLAP = 1 << 1	# Check for overlapping entries first.
+OFPFF_EMERG = 1 << 2	# Ramark this is for emergency.
+
+_OFP_FLOW_MOD_PACK_STR0 = 'QHHHHIHH'
+OFP_FLOW_MOD_PACK_STR = '!' + _OFP_MATCH_PACK_STR + _OFP_FLOW_MOD_PACK_STR0
+OFP_FLOW_MOD_PACK_STR0 = '!' + _OFP_FLOW_MOD_PACK_STR0
+OFP_FLOW_MOD_SIZE = 72
+assert calcsize(OFP_FLOW_MOD_PACK_STR) + OFP_HEADER_SIZE == OFP_FLOW_MOD_SIZE
+
+# enum ofp_flow_removed_reason
+OFPRR_IDLE_TIMEOUT = 0	# Flow idle time exceeded idle_timeout.
+OFPRR_HARD_TIMEOUT = 1	# Time exceeded hard_timeout.
+OFPRR_DELETE = 2	# Evicted by a DELETE flow mod.
+
+_OFP_FLOW_REMOVED_PACK_STR0 = 'QHBxIIH2xQQ'
+OFP_FLOW_REMOVED_PACK_STR = '!' + _OFP_MATCH_PACK_STR + \
+                            _OFP_FLOW_REMOVED_PACK_STR0
+OFP_FLOW_REMOVED_PACK_STR0 = '!' + _OFP_FLOW_REMOVED_PACK_STR0
+OFP_FLOW_REMOVED_SIZE = 88
+assert (calcsize(OFP_FLOW_REMOVED_PACK_STR) + OFP_HEADER_SIZE ==
+        OFP_FLOW_REMOVED_SIZE)
+
+
+# enum ofp_error_type
+OFPET_HELLO_FAILED = 0	# Hello protocol failed.
+OFPET_BAD_REQUEST = 1	# Request was not understood.
+OFPET_BAD_ACTION = 2	# Error in action description.
+OFPET_FLOW_MOD_FAILED = 3	# Problem modifying flow entry.
+OFPET_PORT_MOD_FAILED = 4	# OFPT_PORT_MOD failed.
+OFPET_QUEUE_OP_FAILED = 5	# Queue operation failed.
+
+# enum ofp_hello_failed_code
+OFPHFC_INCOMPATIBLE = 0	# No compatible version.
+OFPHFC_EPERM = 1	# Permissions error.
+
+# enum ofp_bad_request_code
+OFPBRC_BAD_VERSION = 0	# ofp_header.version not supported.
+OFPBRC_BAD_TYPE = 1	# ofp_header.type not supported.
+OFPBRC_BAD_STAT = 2	# ofp_stats_msg.type not supported.
+OFPBRC_BAD_VENDOR = 3	# Vendor not supported (in ofp_vendor_header
+                        # or ofp_stats_msg).
+OFPBRC_BAD_SUBTYPE = 4	# Vendor subtype not supported.
+OFPBRC_EPERM = 5	# Permissions error.
+OFPBRC_BAD_LEN = 6	# Wrong request length for type.
+OFPBRC_BUFFER_EMPTY = 7	# Specified buffer has already been used.
+OFPBRC_BUFFER_UNKNOWN = 8	# Specified buffer does not exist.
+
+# enum ofp_bad_action_code
+OFPBAC_BAD_TYPE = 0	# Unknown action type.
+OFPBAC_BAD_LEN = 1	# Length problem in actions.
+OFPBAC_BAD_VENDOR = 2	# Unknown vendor id specified.
+OFPBAC_BAD_VENDOR_TYPE = 3	# Unknown action type for vendor id.
+OFPBAC_BAD_OUT_PORT = 4	# Problem validating output action.
+OFPBAC_BAD_ARGUMENT = 5	# Bad action argument.
+OFPBAC_EPERM = 6	# Permissions error.
+OFPBAC_TOO_MANY = 7	# Can't handle this many actions.
+OFPBAC_BAD_QUEUE = 8	# Problem validating output queue.
+
+# enum ofp_flow_mod_failed_code
+OFPFMFC_ALL_TABLES_FULL = 0	# Flow not added because of full tables.
+OFPFMFC_OVERLAP = 1	# Attempted to add overlapping flow with
+                        # CHECK_OVERLAP flags set.
+OFPFMFC_EPERM = 2	# Permissions error.
+OFPFMFC_BAD_EMERG_TIMEOUT = 3	# Flow not added because of non-zero idle/hard
+                                # timeout.
+OFPFMFC_BAD_COMMAND = 4	# Unknown command.
+OFPFMFC_UNSUPPORTED = 5	# Unsupported action list - cannot process in
+                        # the order specified.
+
+# enum ofp_port_mod_failed_code
+OFPPMFC_BAD_PORT = 0	# Specified port does not exist.
+OFPPMFC_BAD_HW_ADDR = 1	# Specified hardware address is wrong.
+
+# enum ofp_queue_op_failed_code
+OFPQOFC_BAD_PORT = 0	# Invalid port (or port does not exist).
+OFPQOFC_BAD_QUEUE = 1	# Queue does not exist.
+OFPQOFC_EPERM = 2	# Permissions error.
+
+OFP_ERROR_MSG_PACK_STR = '!HH'
+OFP_ERROR_MSG_SIZE = 12
+assert calcsize(OFP_ERROR_MSG_PACK_STR) + OFP_HEADER_SIZE == OFP_ERROR_MSG_SIZE
+
+# enum ofp_stats_types
+OFPST_DESC = 1
+OFPST_FLOW = 2
+OFPST_AGGREGATE = 3
+OFPST_TABLE = 4
+OFPST_PORT = 5
+OFPST_QUEUE = 6
+OFPST_VENDOR = 0xffff
+
+_OFP_STATS_MSG_PACK_STR = 'HH'
+OFP_STATS_MSG_PACK_STR = '!' + _OFP_STATS_MSG_PACK_STR
+OFP_STATS_MSG_SIZE = 12
+assert calcsize(OFP_STATS_MSG_PACK_STR) + OFP_HEADER_SIZE == OFP_STATS_MSG_SIZE
+
+# enum ofp_stats_reply_flags
+OFPSF_REPLY_MORE = 1 << 0	# More replies to follow.
+
+# define constants
+DESC_STR_LEN = 256
+DESC_STR_LEN_STR = str(DESC_STR_LEN)
+SERIAL_NUM_LEN = 32
+SERIAL_NUM_LEN_STR = str(SERIAL_NUM_LEN)
+
+OFP_DESC_STATS_PACK_STR = '!' + \
+                          DESC_STR_LEN_STR + 'c' + \
+                          DESC_STR_LEN_STR + 'c' + \
+                          DESC_STR_LEN_STR + 'c' + \
+                          SERIAL_NUM_LEN_STR + 'c' + \
+                          DESC_STR_LEN_STR + 'c'
+OFP_DESC_STATS_SIZE = 1068
+assert (calcsize(OFP_DESC_STATS_PACK_STR) + OFP_STATS_MSG_SIZE ==
+        OFP_DESC_STATS_SIZE)
+
+OFP_FLOW_STATS_REQUEST_PACK_STR = '!' + _OFP_MATCH_PACK_STR + 'BxH'
+OFP_FLOW_STATS_REQUEST_SIZE = 56
+assert (calcsize(OFP_FLOW_STATS_REQUEST_PACK_STR) + OFP_STATS_MSG_SIZE ==
+        OFP_FLOW_STATS_REQUEST_SIZE)
+
+OFP_FLOW_STATS_PACK_STR = '!HBx' + _OFP_MATCH_PACK_STR + 'IIHHH6xQQQ'
+OFP_FLOW_STATS_SIZE = 88
+assert calcsize(OFP_FLOW_STATS_PACK_STR) == OFP_FLOW_STATS_SIZE
+
+OFP_AGGREGATE_STATS_REPLY_PACK_STR = '!QQI4x'
+OFP_AGGREGATE_STATS_REPLY_SIZE = 36
+assert (calcsize(OFP_AGGREGATE_STATS_REPLY_PACK_STR) +
+        OFP_STATS_MSG_SIZE == OFP_AGGREGATE_STATS_REPLY_SIZE)
+
+OFP_TABLE_STATS_PACK_STR = '!B3x' + OFP_MAX_TABLE_NAME_LEN_STR + 'cIIIQQ'
+OFP_TABLE_STATS_SIZE = 64
+assert calcsize(OFP_TABLE_STATS_PACK_STR) == OFP_TABLE_STATS_SIZE
+
+OFP_PORT_STATS_REQUEST_PACK_STR = '!H6x'
+OFP_PORT_STATS_REQUEST_SIZE = 20
+assert (calcsize(OFP_PORT_STATS_REQUEST_PACK_STR) + OFP_STATS_MSG_SIZE ==
+        OFP_PORT_STATS_REQUEST_SIZE)
+
+OFP_PORT_STATS_PACK_STR = '!H6xQQQQQQQQQQQQ'
+OFP_PORT_STATS_SIZE = 104
+assert calcsize(OFP_PORT_STATS_PACK_STR) == OFP_PORT_STATS_SIZE
+
+OFPQ_ALL = 0xffffffff
+
+OFP_QUEUE_STATS_PACK_STR = '!H2xIQQQ'
+OFP_QUEUE_STATS_SIZE = 32
+assert calcsize(OFP_QUEUE_STATS_PACK_STR) == OFP_QUEUE_STATS_SIZE
+
+OFP_VENDOR_STATS_MSG_PACK_STR = '!I'
+OFP_VENDOR_STATS_MSG_SIZE = 16
+assert (calcsize(OFP_VENDOR_STATS_MSG_PACK_STR) + OFP_STATS_MSG_SIZE ==
+        OFP_VENDOR_STATS_MSG_SIZE)
+
+OFP_VENDOR_HEADER_PACK_STR = '!I'
+OFP_VENDOR_HEADER_SIZE = 12
+assert (calcsize(OFP_VENDOR_HEADER_PACK_STR) + OFP_HEADER_SIZE ==
+        OFP_VENDOR_HEADER_SIZE)
diff --git a/ryu/ofproto/ofproto_v1_0_parser.py b/ryu/ofproto/ofproto_v1_0_parser.py
new file mode 100644
index 00000000..e1fdc6a9
--- /dev/null
+++ b/ryu/ofproto/ofproto_v1_0_parser.py
@@ -0,0 +1,542 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import collections
+import struct
+
+from . import ofproto_parser
+from . import ofproto_v1_0
+
+import logging
+LOG = logging.getLogger('ryu.ofproto.ofproto_v1_0_parser')
+
+_MSG_PARSERS = {}
+
+
+def _set_msg_type(msg_type):
+    def _set_cls_msg_type(cls):
+        cls.cls_msg_type = msg_type
+        return cls
+    return _set_cls_msg_type
+
+
+def _register_parser(cls):
+    '''class decorator to register msg parser'''
+    assert cls.cls_msg_type is not None
+    assert cls.cls_msg_type not in _MSG_PARSERS
+    _MSG_PARSERS[cls.cls_msg_type] = cls.parser
+    return cls
+
+
+@ofproto_parser.register_msg_parser(ofproto_v1_0.OFP_VERSION)
+def msg_parser(datapath, version, msg_type, msg_len, xid, buf):
+    parser = _MSG_PARSERS.get(msg_type)
+    return parser(datapath, version, msg_type, msg_len, xid, buf)
+
+
+class MsgBase(object):
+    def __init__(self, datapath):
+        self.datapath = datapath
+        self.version = None
+        self.msg_type = None
+        self.msg_len = None
+        self.xid = None
+        self.buf = None
+
+    def set_headers(self, version, msg_type, msg_len, xid):
+        assert msg_type == self.cls_msg_type
+
+        self.version = version
+        self.msg_type = msg_type
+        self.msg_len = msg_len
+        self.xid = xid
+
+    def set_buf(self, buf):
+        self.buf = buffer(buf)
+
+    def __str__(self):
+        return 'version: 0x%x msg_type 0x%x xid 0x%x' % (self.version,
+                                                         self.msg_type,
+                                                         self.xid)
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = cls(datapath)
+        msg.set_headers(version, msg_type, msg_len, xid)
+        msg.set_buf(buf)
+        return msg
+
+    def _serialize_pre(self):
+        assert self.version is None
+        assert self.msg_type is None
+        assert self.buf is None
+
+        self.version = ofproto_v1_0.OFP_VERSION
+        self.msg_type = self.cls_msg_type
+        self.buf = bytearray().zfill(ofproto_v1_0.OFP_HEADER_SIZE)
+
+    def _serialize_header(self):
+        # buffer length is determined after trailing data is formated.
+        assert self.version is not None
+        assert self.msg_type is not None
+        assert self.msg_len is None
+        assert self.xid is None
+        assert self.buf is not None
+        assert len(self.buf) >= ofproto_v1_0.OFP_HEADER_SIZE
+
+        self.msg_len = len(self.buf)
+        self.xid = 0  # TODO:XXX
+
+        struct.pack_into(ofproto_v1_0.OFP_HEADER_PACK_STR, self.buf, 0,
+                         self.version, self.msg_type, self.msg_len, self.xid)
+
+    def _serialize_body(self):
+        pass
+
+    def serialize(self):
+        self._serialize_pre()
+        self._serialize_body()
+        self._serialize_header()
+
+
+def _pack_into(fmt, buf, offset, *args):
+    if len(buf) < offset:
+        buf += bytearray().zfill(offset - len(buf))
+
+    if len(buf) == offset:
+        buf += struct.pack(fmt, *args)
+        return
+
+    needed_len = offset + struct.calcsize(fmt)
+    if len(buf) < needed_len:
+        buf += bytearray().zfill(needed_len - len(buf))
+
+    struct.pack_into(fmt, buf, offset, *args)
+
+
+def _str_attr(msg, buf, attr_list):
+    for attr in attr_list:
+        val = getattr(msg, attr, None)
+        if val is not None:
+            buf += ' %s %s' % (attr, val)
+
+    return buf
+
+
+#
+# common structures
+#
+
+class OFPPhyPort(collections.namedtuple('OFPPhyPort', (
+    'port_no', 'hw_addr', 'name', 'config', 'state', 'curr', 'advertised',
+    'supported', 'peer'))):
+
+    @classmethod
+    def parser(cls, buf, offset):
+        port = struct.unpack_from(ofproto_v1_0.OFP_PHY_PORT_PACK_STR,
+                                  buf, offset)
+        return cls(*port)
+
+
+class OFPMatch(collections.namedtuple('OFPMatchBase', (
+            'wildcards', 'in_port', 'dl_src', 'dl_dst', 'dl_vlan',
+            'dl_vlan_pcp', 'dl_type', 'nw_tos', 'nw_proto',
+            'nw_src', 'nw_dst', 'tp_src', 'tp_dst'))):
+
+    def serialize(self, buf, offset):
+        _pack_into(ofproto_v1_0.OFP_MATCH_PACK_STR, buf, offset, *self)
+
+    @classmethod
+    def parse(cls, buf, offset):
+        match = struct.unpack_from(ofproto_v1_0.OFP_MATCH_PACK_STR,
+                                   buf, offset)
+        return cls(*match)
+
+
+class OFPActionHeader(object):
+    def __init__(self, type, len):
+        self.type = type
+        self.len = len
+
+    def serlize(self, buf, offset):
+        _pack_into(ofproto_v1_0.OFP_ACTION_HEADER_PACK_STR,
+                   buf, offset, self.type, self.len)
+
+
+class OFPActionOutput(OFPActionHeader):
+    def __init__(self, port, max_len=0):
+        super(OFPActionOutput,
+              self).__init__(ofproto_v1_0.OFPAT_OUTPUT,
+                             ofproto_v1_0.OFP_ACTION_OUTPUT_LEN)
+        self.port = port
+        self.max_len = max_len
+
+    def serialize(self, buf, offset):
+        _pack_into(ofproto_v1_0.OFP_ACTION_OUTPUT_PACK_STR,
+                   buf, offset, self.type, self.len, self.port, self.max_len)
+
+
+# TODO:XXX more actions
+
+
+#
+# Symmetric messages
+# parser + serializer
+#
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_HELLO)
+class OFPHello(MsgBase):
+    def __init__(self, datapath):
+        super(OFPHello, self).__init__(datapath)
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_ERROR)
+class OFPErrorMsg(MsgBase):
+    def __init__(self, datapath):
+        super(OFPErrorMsg, self).__init__(datapath)
+        self.type = None
+        self.code = None
+        self.data = None
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPErrorMsg, cls).parser(datapath, version, msg_type,
+                                             msg_len, xid, buf)
+        msg.type, msg.code = struct.unpack_from(
+            ofproto_v1_0.OFP_ERROR_MSG_PACK_STR, msg.buf,
+            ofproto_v1_0.OFP_HEADER_SIZE)
+        msg.data = msg.buf[ofproto_v1_0.OFP_ERROR_MSG_SIZE:]
+        return msg
+
+    def _serialize_body(self):
+        assert self.data is not None
+        _pack_into(ofproto_v1_0.OFP_ERROR_MSG_PACK_STR, self.buf,
+                   ofproto_v1_0.OFP_HEADER_SIZE, self.type, self.code)
+        self.buf += self.data
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_ECHO_REQUEST)
+class OFPEchoRequest(MsgBase):
+    def __init__(self, datapath):
+        super(OFPEchoRequest, self).__init__(datapath)
+        self.data = None
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPEchoRequest, cls).parser(datapath, version, msg_type,
+                                                msg_len, xid, buf)
+        msg.data = msg.buf[ofproto_v1_0.OFP_HEADER_SIZE:]
+        return msg
+
+    def _serialize_body(self):
+        assert self.data is not None
+        self.buf += self.data
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_ECHO_REPLY)
+class OFPEchoReply(MsgBase):
+    def __init__(self, datapath):
+        super(OFPEchoReply, self).__init__(datapath)
+        self.data = None
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPEchoReply, cls).parser(datapath, version, msg_type,
+                                              msg_len, xid, buf)
+        msg.data = msg.buf[ofproto_v1_0.OFP_HEADER_SIZE:]
+        return msg
+
+    def _serialize_body(self):
+        assert self.data is not None
+        self.buf += self.data
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_VENDOR)
+class OFPVendor(MsgBase):
+    def __init__(self, datapath):
+        super(OFPVendor, self).__init__(datapath)
+        self.data = None
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPVendor, cls).parser(datapath, version, msg_type,
+                                           msg_len, xid, buf)
+        msg.vendor = struct.unpack_from(
+            ofproto_v1_0.OFP_VENDOR_HEADER_PACK_STR, msg.buf,
+            ofproto_v1_0.OFP_HEADER_SIZE)
+        msg.data = msg.buf[ofproto_v1_0.OFP_VENDOR_HEADER_SIZE:]
+        return msg
+
+    def _serialize_body(self):
+        assert self.data is not None
+        _pack_into(ofproto_v1_0.OFP_VENDOR_HEADER_PACK_STR,
+                   self.buf, ofproto_v1_0.OFP_HEADER_SIZE, self.vendor)
+        self.buf += self.data
+
+
+#
+# asymmetric message (datapath -> controller)
+# parser only
+#
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_FEATURES_REPLY)
+class OFPSwitchFeatures(MsgBase):
+    def __init__(self, datapath):
+        super(OFPSwitchFeatures, self).__init__(datapath)
+
+    def __str__(self):
+        buf = super(OFPSwitchFeatures, self).__str__() + ' port'
+        for port_no, p in getattr(self, 'ports', {}).items():
+            buf += ' ' + str(p)
+        return buf
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPSwitchFeatures, cls).parser(datapath, version, msg_type,
+                                                   msg_len, xid, buf)
+        (msg.datapath_id,
+         msg.n_buffers,
+         msg.n_tables,
+         msg.capabilities,
+         msg.actions) = struct.unpack_from(
+            ofproto_v1_0.OFP_SWITCH_FEATURES_PACK_STR, msg.buf,
+            ofproto_v1_0.OFP_HEADER_SIZE)
+
+        msg.ports = {}
+        n_ports = ((msg_len - ofproto_v1_0.OFP_SWITCH_FEATURES_SIZE) /
+                   ofproto_v1_0.OFP_PHY_PORT_SIZE)
+        offset = ofproto_v1_0.OFP_SWITCH_FEATURES_SIZE
+        for i in range(n_ports):
+            port = OFPPhyPort.parser(msg.buf, offset)
+            # print 'port = %s' % str(port)
+            msg.ports[port.port_no] = port
+            offset += ofproto_v1_0.OFP_PHY_PORT_SIZE
+
+        return msg
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_PORT_STATUS)
+class OFPPortStatus(MsgBase):
+    def __init__(self, datapath):
+        super(OFPPortStatus, self).__init__(datapath)
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPPortStatus, cls).parser(datapath, version, msg_type,
+                                                   msg_len, xid, buf)
+        msg.reason = struct.unpack_from(
+            ofproto_v1_0.OFP_PORT_STATUS_PACK_STR,
+            msg.buf, ofproto_v1_0.OFP_HEADER_SIZE)[0]
+        msg.desc = OFPPhyPort.parser(msg.buf,
+                                     ofproto_v1_0.OFP_PORT_STATUS_DESC_OFFSET)
+        return msg
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_PACKET_IN)
+class OFPPacketIn(MsgBase):
+    def __init__(self, datapath):
+        super(OFPPacketIn, self).__init__(datapath)
+
+    def __str__(self):
+        buf = super(OFPPacketIn, self).__str__()
+        return _str_attr(self, buf,
+                         ('buffer_id', 'total_len', 'in_port', 'reason'))
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPPacketIn, cls).parser(datapath, version, msg_type,
+                                             msg_len, xid, buf)
+        (msg.buffer_id,
+         msg.total_len,
+         msg.in_port,
+         msg.reason) = struct.unpack_from(
+            ofproto_v1_0.OFP_PACKET_IN_PACK_STR,
+            msg.buf, ofproto_v1_0.OFP_HEADER_SIZE)
+        msg.data = msg.buf[ofproto_v1_0.OFP_PACKET_IN_DATA_OFFSET:]
+        return msg
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_GET_CONFIG_REPLY)
+class OFPSwitchConfig(MsgBase):
+    def __init__(self, datapath):
+        super(OFPSwitchConfig, self).__init__(datapath)
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPSwitchConfig, cls).parser(datapath, version, msg_type,
+                                                 msg_len, xid, buf)
+        (msg.flags, msg.miss_send_len) = struct.unpack_from(
+            ofproto_v1_0.OFP_SWITCH_CONFIG_PACK_STR,
+            msg.buf, ofproto_v1_0.OFP_HEADER_SIZE)
+        return msg
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_BARRIER_REPLY)
+class OFPBarrierReply(MsgBase):
+    def __init__(self, datapath):
+        super(OFPBarrierReply, self).__init__(datapath)
+
+
+@_register_parser
+@_set_msg_type(ofproto_v1_0.OFPT_FLOW_REMOVED)
+class OFPFlowRemoved(MsgBase):
+    def __init__(self, datapath):
+        super(OFPFlowRemoved, self).__init__(datapath)
+
+    def __str__(self):
+        buf = super(OFPFlowRemoved, self).__str__()
+        return _str_attr(self, buf,
+                         ('match', 'cookie', 'priority', 'reason',
+                          'duration_sec', 'duration_nsec',
+                          'idle_timeout', 'packet_count', 'idle_count'))
+
+    @classmethod
+    def parser(cls, datapath, version, msg_type, msg_len, xid, buf):
+        msg = super(OFPFlowRemoved, cls).parser(datapath, version, msg_type,
+                                                msg_len, xid, buf)
+
+        msg.match = OFPMatch.parse(msg.buf, ofproto_v1_0.OFP_HEADER_SIZE)
+
+        (msg.cookie,
+         msg.priority,
+         msg.reason,
+         msg.duration_sec,
+         msg.duration_nsec,
+         msg.idle_timeout,
+         msg.packet_count,
+         msg.byte_count) = struct.unpack_from(
+            ofproto_v1_0.OFP_FLOW_REMOVED_PACK_STR0, msg.buf,
+            ofproto_v1_0.OFP_HEADER_SIZE + ofproto_v1_0.OFP_MATCH_SIZE)
+
+        return msg
+
+#
+# controller-to-switch message
+# serializer only
+#
+
+
+@_set_msg_type(ofproto_v1_0.OFPT_FEATURES_REQUEST)
+class OFPFeaturesRequest(MsgBase):
+    def __init__(self, datapath):
+        super(OFPFeaturesRequest, self).__init__(datapath)
+
+
+@_set_msg_type(ofproto_v1_0.OFPT_GET_CONFIG_REQUEST)
+class OFPGetConfigRequest(MsgBase):
+    def __init__(self, datapath):
+        super(OFPGetConfigRequest, self).__init__(datapath)
+
+
+@_set_msg_type(ofproto_v1_0.OFPT_SET_CONFIG)
+class OFPSetConfig(MsgBase):
+    def __init__(self, datapath, flags=None, miss_send_len=None):
+        super(OFPSetConfig, self).__init__(datapath)
+        self.flags = flags
+        self.miss_send_len = miss_send_len
+
+    def _serialize_body(self):
+        assert self.flags is not None
+        assert self.miss_send_len is not None
+        _pack_into(ofproto_v1_0.OFP_SWITCH_CONFIG_PACK_STR,
+                   self.buf, ofproto_v1_0.OFP_HEADER_SIZE,
+                   self.flags, self.miss_send_len)
+
+
+@_set_msg_type(ofproto_v1_0.OFPT_PACKET_OUT)
+class OFPPacketOut(MsgBase):
+    def __init__(self, datapath, buffer_id=None, in_port=None, actions=None,
+                 data=None):
+        super(OFPPacketOut, self).__init__(datapath)
+        self.buffer_id = buffer_id
+        self.in_port = in_port
+        self.actions_len = None
+        self.actions = actions
+        self.data = data
+
+    def _serialize_body(self):
+        assert self.buffer_id is not None
+        assert self.in_port is not None
+        assert self.actions_len is None
+        assert self.actions is not None
+
+        self.actions_len = 0
+        offset = ofproto_v1_0.OFP_PACKET_OUT_SIZE
+        for a in self.actions:
+            a.serialize(self.buf, offset)
+            offset += a.len
+            self.actions_len += a.len
+
+        if self.data is not None:
+            assert self.buffer_id == -1
+            self.buf += self.data
+
+        _pack_into(ofproto_v1_0.OFP_PACKET_OUT_PACK_STR,
+                   self.buf, ofproto_v1_0.OFP_HEADER_SIZE,
+                   self.buffer_id, self.in_port, self.actions_len)
+
+
+@_set_msg_type(ofproto_v1_0.OFPT_FLOW_MOD)
+class OFPFlowMod(MsgBase):
+    def __init__(self, datapath, match=None, cookie=None,
+                 command=None, idle_timeout=None, hard_timeout=None,
+                 priority=None, buffer_id=None, out_port=None,
+                 flags=None, actions=None):
+        super(OFPFlowMod, self).__init__(datapath)
+        self.match = match
+        self.cookie = cookie
+        self.command = command
+        self.idle_timeout = idle_timeout
+        self.hard_timeout = hard_timeout
+        self.priority = priority
+        self.buffer_id = buffer_id
+        self.out_port = out_port
+        self.flags = flags
+        self.actions = actions
+
+    def _serialize_body(self):
+        offset = ofproto_v1_0.OFP_HEADER_SIZE
+        self.match.serialize(self.buf, offset)
+
+        offset += ofproto_v1_0.OFP_MATCH_SIZE
+        _pack_into(ofproto_v1_0.OFP_FLOW_MOD_PACK_STR0, self.buf, offset,
+                   self.cookie, self.command,
+                   self.idle_timeout, self.hard_timeout,
+                   self.priority, self.buffer_id, self.out_port,
+                   self.flags)
+
+        offset = ofproto_v1_0.OFP_FLOW_MOD_SIZE
+        if self.actions is not None:
+            for a in self.actions:
+                a.serialize(self.buf, offset)
+                offset += a.len
+
+
+@_set_msg_type(ofproto_v1_0.OFPT_BARRIER_REQUEST)
+class OFPBarrierRequest(MsgBase):
+    def __init__(self, datapath):
+        super(OFPBarrierRequest, self).__init__(datapath)
diff --git a/ryu/utils.py b/ryu/utils.py
new file mode 100644
index 00000000..c3f3fe52
--- /dev/null
+++ b/ryu/utils.py
@@ -0,0 +1,62 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import inspect
+import logging
+import os
+import sys
+
+LOG = logging.getLogger('ryu.utils')
+
+def import_module(modname):
+    (f, s, t) = modname.rpartition('.')
+    mod = __import__(modname, fromlist=[f])
+    return mod
+
+
+def import_object(modname):
+    try:
+        return import_module(modname)
+    except ImportError:
+        (from_mod, sep, target) = modname.rpartition('.')
+        mod = import_module(from_mod)
+        return getattr(mod, target)
+
+
+RYU_DEFAULT_FLAG_FILE = ('ryu.conf', 'etc/ryu/ryu.conf' '/etc/ryu/ryu.conf')
+
+
+def find_flagfile(default_path=RYU_DEFAULT_FLAG_FILE):
+    if '--flagfile' in sys.argv:
+        return
+
+    script_dir = os.path.dirname(inspect.stack()[-1][1])
+
+    for filename in RYU_DEFAULT_FLAG_FILE:
+        if not os.path.abspath(filename):
+            if os.path.exists(filename):
+                # try relative to current path
+                filename = os.path.abspath(filename)
+            elif os.path.exists(os.path.join(script_dir, filename)):
+                # try relative to script dir
+                filename = os.path.join(script_dir, filename)
+
+        if not os.path.exists(filename):
+            continue
+
+        flagfile = '--flagfile=%s' % filename
+        sys.argv.insert(1, flagfile)
+        LOG.debug('flagfile = %s', filename)
+        return
diff --git a/setup.cfg b/setup.cfg
new file mode 100644
index 00000000..46409041
--- /dev/null
+++ b/setup.cfg
@@ -0,0 +1 @@
+# TODO
diff --git a/setup.py b/setup.py
new file mode 100644
index 00000000..41583033
--- /dev/null
+++ b/setup.py
@@ -0,0 +1,38 @@
+# Copyright (C) 2011 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2011 Isaku Yamahata <yamahata at valinux co jp>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+
+from setuptools import find_packages
+from setuptools import setup
+
+README = os.path.join(os.path.dirname(__file__), 'README.rst')
+long_description = open(README).read() + '\n\n'
+
+setup(name='ryu',
+      version='0.1',
+      description=("Ryu Network Operating System"),
+      long_description=long_description,
+      keywords='openflow openvswitch openstack',
+      url='http://www.osrg.net/ryu/',
+#      author='',
+      autor_email='ryu-devel@lists.sourceforge.net',
+      license='GPL v3 only',
+      packages=find_packages(),
+      scripts=['bin/ryu-manager',
+               'bin/ryu-client'],
+      data_files=[('etc/ryu', ['etc/ryu/ryu.conf'])],
+#      install_requires=[]
+      )