- OpenFlow Reference Release v0.1.5 <http://openflowswitch.org>
+ OpenFlow Reference Release <http://openflowswitch.org>
What is OpenFlow?
-----------------
simple Ethernet flow switch that exposes a standardized interface for
adding and removing flow entries.
-An OpenFlow Switch consists of three parts: (1) A Flow Table in which
-each flow entry is associated with an action telling the switch how to
-process the flow, (2) A Secure Channel connecting the switch to a remote
-process (a controller), allowing commands and packets to be sent between
-the controller and the switch, and (3) An OpenFlow Protocol
-implementation, providing an open and standard way for a controller to
-talk to the switch.
+An OpenFlow switch consists of three parts: (1) A "flow table" in
+which each flow entry is associated with an action telling the switch
+how to process the flow, (2) a "secure channel" connecting the switch
+to a remote process (a controller), allowing commands and packets to
+be sent between the controller and the switch, and (3) an OpenFlow
+protocol implementation, providing an open and standard way for a
+controller to talk to the switch.
-An OpenFlow Switch can thus serve as a simple datapath element that
+An OpenFlow switch can thus serve as a simple datapath element that
forwards packets between ports according to flow actions defined by
the controller using OpenFlow commands. Example actions are:
- Drop this flow's packets
- Encapsulate and forward this flow's packets to the controller.
-The OpenFlow Switch is defined in detail in the OpenFlow Switch
+The OpenFlow switch is defined in detail in the OpenFlow switch
Specification [2].
What's here?
------------
-This software is a reference implementation of an OpenFlow Switch kernel
-module for the Linux operating system, a secure channel implementation,
-and an example controller that performs switching with MAC learning.
+This distribution includes two reference implementations of an
+OpenFlow switch. The first implementation, which is closely tied to
+Linux because it is partially implemented in the Linux kernel, has the
+following components:
-The rest of this file contains the following sections:
+ - A Linux kernel module that implements the flow table and
+ OpenFlow protocol, in the datapath directory.
- - Description of the directory hierarchy
- - Platform support
- - Quickstart build and install instructions
- - Shortcomings
- - References
+ - secchan, a program that implements the secure channel
+ component of the reference switch.
-Directory Hierarchy
--------------------
+ - dpctl, a tool for configuring the kernel module.
- Source:
+The second implementation has the following components:
- datapath/ Linux kernel module implementing an OpenFlow Flow Table
- that incoming packets are checked against. The
- kernel module uses netlink (a socket protocol for
- user-kernel communication, described in RFC 3549) to
- pass OpenFlow messages with the secure channel to be
- relayed to the controller.
+ - udatapath, which implements the same functionality as the
+ Linux kernel module in userspace, at a cost in performance.
- secchan/ A Secure Channel that connects to a kernel datapath
- via netlink and a remote controller via TCP,
- relaying OpenFlow packets received on one end to the
- other. (The current implementation does not
- support SSL, but this will be added in future releases.)
+ - secchan, a program that implements the secure channel
+ component of the reference switch (the same program used in
+ the kernel-based implementation).
- controller/ A simple controller that connects to a datapath via
- a Secure Channel, commanding the datapath to act as
- a regular MAC learning switch.
+This distribution includes some additional software as well:
- utilities/ Contains the sorce for "dpctl", a command-line utility
- for controlling the OpenFlow datapath kernel module.
- With it, you can add physical ports to the datapath,
- add flows, monitor received packets, and query the
- datapath state.
+ - controller, a simple program that connects to any number of
+ OpenFlow switches, commanding them to act as regular MAC
+ learning switches.
- include/ Header files common to the datapath, secure channel,
- and controller components.
+ - vlogconf, a utility that can adjust the logging levels of a
+ running secchan or controller.
- lib/ Implementation files common to the datapath, secure
- channel, and controller components.
+ - ofp-pki, a utility for creating and managing the public-key
+ infrastructure for OpenFlow switches.
- third-party/ Contains third-party software that may be useful for
- debugging. Currently, it only contains a patch to
- allow tcpdump to parse OpenFlow messages.
-
- Documentation:
+ - A patch to tcpdump that enables it to parse OpenFlow
+ messages.
- README Text file describing this OpenFlow implementation,
- aka this document.
-
- INSTALLATION Detailed configure, build, and installation
- instructions
-
- man/ Man pages describing how to administer datapath,
- secure channel, and controller.
+For installation instructions, read INSTALL. Each userspace program
+is also accompanied by a manpage.
Platform support
----------------
- The datapath kernel module supports Linux 2.6.15 and above, however,
- testing has focused on Linux 2.6.23. Support for Linux 2.4.20 and
- above is also in place, although testing has focused on Linux 2.6.
-
- Components have been built and tested on Debian and Ubuntu.
-
- If you are able to build/run the code on platforms not mentioned
- here, or have problems with supported system, please report your
- experiences to:
-
- <info@openflowswitch.org>
-
- GCC is required for compilation.
-
-
-Building and Installing (Quick Start)
--------------------------------------
-
- Building the datapath module requires that the source for the
- currently running Linux kernel be installed on the machine and
- been configured.
-
- The following instructions assume the Linux 2.6 source is located in
- /usr/src/linux-2.6.23 and Linux 2.4 in /usr/src/linux-2.4.35
-
- 1. ./configure the package, passing the location of one or more
- kernel source trees on the command line:
-
- For example, if compiling for Linux 2.6:
- % ./configure --with-l26=/usr/src/linux-2.6.23
+Other than the Linux kernel module and userspace switch
+implementation, the software in the OpenFlow distribution should
+compile under Unix-like environments such as Linux, FreeBSD, Mac OS X,
+and Solaris. Our primary test environment is Debian GNU/Linux.
+Please contact us with portability-related bug reports or patches.
- Or compiling for Linux 2.4:
- % ./configure --with-l24=/usr/src/linux-2.4.35
+The Linux kernel module is, of course, Linux-specific, and the dpctl
+utility will not be useful without the kernel module. The testing of
+the kernel module has focused on Linux 2.6.26. Linux 2.6 releases
+from 2.6.15 onward and Linux 2.4 releases from 2.4.20 onward should
+also work.
- 2. Run make:
-
- % make
-
- The following binaries should be built.
-
- Datapath kernel module:
- ./datapath/linux-2.6/openflow_mod.ko (If compiling for Linux 2.6)
- ./datapath/linux-2.4/openflow_mod.o (If compiling for Linux 2.4)
-
- Secure channel executable:
- ./secchan/secchan
-
- Controller executable:
- ./controller/controller
-
- dpctl utility:
- ./utility/dpctl
-
- 3. Optionally you can "make install" to install binaries and the
- man pages (/usr/local/ is the default prefix). If you just want
- access to the man pages without installing, set your MANPATH to
- include the openflow/ source root.
-
- 4. Insert the datapath kernel module into the running Linux instance.
-
- (Linux 2.6)
- % insmod datapath/linux-2.6/openflow_mod.ko
-
- (Linux 2.4)
- % insmod datapath/linux-2.4/openflow_mod.o
-
- 5. Create datapaths by running dpctl on the Linux host (see man
- dpctl(8)). Start the controller on a remote host with
- controller (see man controller(8)). Start the Secure Channel
- on the datapath host to connect the datapath to the controller
- with secchan(see man secchan(8)).
-
- For more detailed installation instructions, refer to [3].
+The userspace datapath implementation should be easy to port to
+Unix-like systems. The interface to network devices, in netdev.c, is
+the code most likely to need changes. So far, only Linux is
+supported. We welcome ports to other platforms.
+GCC is the expected compiler.
Bugs/Shortcomings
-----------------
-- The current flowtable does not support all statistics messages
- mentioned in the Type 0 OpenFlow spec
-- The secure channel and sample controller don't support SSL
-- The flowtable does not support the "normal processing" action
-- Configure/build system does not support separate build directory for
- the datapath. ./configure must be run from the source root.
-- dpctl dump-flows may freeze when large numbers of flows are in the
- flow table. This has no affect on the datapath
+- The flow table does not support the "normal processing" action.
References
----------
[1] OpenFlow: Enabling Innovation in College Networks. Whitepaper.
- <http://openflowswitch.org/alpha/openflow-wp-v0.1.pdf>
+ <http://openflowswitch.org/documents/openflow-wp-latest.pdf>
[2] OpenFlow Switch Specification.
- <http://openflowswitch.org/alpha/openflow-spec-v0.2.pdf>
-
- [3] Installation Instructions: INSTALL
+ <http://openflowswitch.org/documents/openflow-spec-latest.pdf>
Contact
-------
e-mail: info@openflowswitch.org
-www: http://openflowswitch.org/alpha/
+www: http://openflowswitch.org/
git://git.onelab.eu / sliver-openvswitch.git / blobdiff