1 OpenFlow Reference Release <http://openflowswitch.org>
6 OpenFlow is a flow-based switch specification designed to enable
7 researchers to run experiments in live networks. OpenFlow is based on a
8 simple Ethernet flow switch that exposes a standardized interface for
9 adding and removing flow entries.
11 An OpenFlow switch consists of three parts: (1) A "flow table" in
12 which each flow entry is associated with an action telling the switch
13 how to process the flow, (2) a "secure channel" connecting the switch
14 to a remote process (a controller), allowing commands and packets to
15 be sent between the controller and the switch, and (3) an OpenFlow
16 protocol implementation, providing an open and standard way for a
17 controller to talk to the switch.
19 An OpenFlow switch can thus serve as a simple datapath element that
20 forwards packets between ports according to flow actions defined by
21 the controller using OpenFlow commands. Example actions are:
23 - Forward this flow's packets to the given port(s)
24 - Drop this flow's packets
25 - Encapsulate and forward this flow's packets to the controller.
27 The OpenFlow switch is defined in detail in the OpenFlow switch
33 This distribution includes two different reference implementations of
34 an OpenFlow switch. The first implementation, which is closely tied
35 to Linux because it is partially implemented in the Linux kernel, has
36 the following components:
38 - A Linux kernel module that implements the flow table and
39 OpenFlow protocol, in the datapath directory.
41 - secchan, a program that implements the secure channel
42 component of the reference switch.
44 - dpctl, a tool for configuring the kernel module.
46 The second implementation is a single userspace program, named
47 "switch", that integrates all three parts of an OpenFlow switch.
49 This distribution includes some additional software as well:
51 - controller, a simple program that connects to any number of
52 OpenFlow switches, commanding them to act as regular MAC
55 - vlogconf, a utility that can adjust the logging levels of a
56 running secchan or controller.
58 - ofp-pki, a utility for creating and managing the public-key
59 infrastructure for OpenFlow switches.
61 - A patch to tcpdump that enables it to parse OpenFlow
64 For installation instructions, read INSTALL. Each userspace program
65 is also accompanied by a manpage.
70 Other than the Linux kernel module and userspace switch
71 implementation, the software in the OpenFlow distribution should
72 compile under Unix-like environments such as Linux, FreeBSD, Mac OS X,
73 and Solaris. Our primary test environment is Debian GNU/Linux.
74 Please contact us with portability-related bug reports or patches.
76 The Linux kernel module is, of course, Linux-specific, and the secchan
77 and dpctl utilities will not be as useful without the kernel module.
78 The testing of the kernel module has focused on Linux 2.6.23. Linux
79 2.6 releases from 2.6.15 onward and Linux 2.4 releases from 2.4.20
80 onward should also work.
82 The userspace switch implementation should be easy to port to
83 Unix-like systems. The interface to network devices, in netdev.c, is
84 the only code that should need to change. So far, only Linux is
85 supported. We welcome ports to other platforms.
87 GCC is the expected compiler.
92 - The flowtable does not support the "normal processing" action.
97 [1] OpenFlow: Enabling Innovation in College Networks. Whitepaper.
98 <http://openflowswitch.org/documents/openflow-wp-latest.pdf>
100 [2] OpenFlow Switch Specification.
101 <http://openflowswitch.org/documents/openflow-spec-latest.pdf>
106 e-mail: info@openflowswitch.org
107 www: http://openflowswitch.org/