Announcing Floodlight v1.0

After months of collaboration and hard work, I am pleased to announce the release of Floodlight v1.0. Floodlight v1.0 has full support for OpenFlow 1.0 and 1.3 along with experimental support for OpenFlow 1.1, 1.2, and 1.4. Here are the highlights of what Floodlight v1.0 has to offer and how you can get your hands on it:

At it’s core is the OpenFlowJ-Loxigen (or OpenFlowJ-Loxi for short) generated Java library, which among many powerful things abstracts the OpenFlow version behind a common API. Loxigen works by parsing OpenFlow concepts defined as structures in a set of input files. It then generates a set of Java, Python, and C libraries for use in OpenFlow applications. The Loxigen-generated libraries abstract away low-level details and provide a far more pleasant and high-level programming experience for developers. It is straightforward to define each OpenFlow version in Loxigen’s input files, and each OpenFlow version is exposed through a common API, which results in few if not zero application code changes when adding OpenFlow versions. In other words, Loxigen provides a fairly future-proof API for the many OpenFlow versions to come. The Loxigen project is open source and can be found on GitHub here.

Floodlight of course uses the Java library generated by Loxigen, also known as OpenFlowJ-Loxi. Although OpenFlowJ-Loxi is the new heart of the new Floodlight controller, there have been many higher-level changes necessary to accommodate the new library as well as to fix some known bugs and improve the overall performance and capabilities of the Floodlight controller. Many will go unnoticed; however, some will have immediate impact on how your modules interact with the controller core.

For instance, the Floodlight v0.90 and v0.91 (old master) Controller class was, among many things, responsible for managing switches. This responsibility has been relocated from the Controller class to a new class called the OFSwitchManager. It is exposed to modules as a service, the IOFSwitchService. Instead of accessing switches using the IFloodlightProviderService, developers should instead depend on and obtain a reference to the IOFSwitchService.

Furthermore, the Static Flow Pusher and REST API in general has undergone an extensive renovation to enable full OpenFlow 1.3 support. More information on the Static Flow Pusher and its REST API syntax can be found here. Please note any syntax changes from prior Floodlight versions, and be certain to use the correct syntax for your OpenFlow version.

One of the key features of Floodlight v1.0 is its full support for OpenFlow 1.0 and 1.3, complete with an easy-to-use, version-agnostic API. Each OpenFlow version has a factory that can build all types and messages as they are defined for that version of OpenFlow. This allows for a very much improved way to create OpenFlow Messages, Matches, Actions, FlowMods, etc. The creation of many OpenFlow objects has been greatly simplified using builders, all accessible from a common OpenFlow factory interface. All objects produced from builders are immutable, which allows for safer code and makes your applications easier to debug.

To best demonstrate the extent to which constructing and working with OpenFlow concepts such as FlowMods has been improved in Floodlight v1.0, consider the following before and after example.

/* Pre-v1.0 -- the old way to compose an OFFlowMod */
OFFlowMod flow = new OFFlowMod(); // no builder pattern; not immutable
OFMatch match = new OFMatch();
ArrayList<OFAction> actions = new ArrayList<OFAction>();
OFActionOutput outputAction = new OFActionOutput();
match.setInputPort((short) 1); // not type-safe; many OpenFlow concepts are represented as shorts
match.setDataLayerType(Ethernet.TYPE_IPv4);
match.setWildcards(Wildcards.FULL.matchOn(Flag.IN_PORT).matchOn(Flag.DL_TYPE)); // wildcarding necessary
outputAction.setType(OFActionType.OUTPUT);
outputAction.setPort((short) 2); // raw types used; casting required
outputAction.setLength((short) OFActionOutput.MINIMUM_LENGTH);
actions(outputAction);
flow.setBufferId(-1);
flow.setActions(actions);
flow.setMatch(match);
flow.setLengthU(OFFlowMod.MINIMUM_LENGTH + outputAction.getLengthU()); // length must be set correctly
sw.write(flow);
/* Floodlight v1.0 -- the new and improved way to compose an OFFlowMod */
ArrayList<OFAction> actions = new ArrayList<OFAction>();
actions.add(myFactory.actions().buildOutput() // builder pattern used throughout
  .setPort(OFPort.of(1)) // raw types replaced with objects for type-checking and readability
  .build()); // list of immutable OFAction objects
OFFlowAdd flow = myFactory.buildFlowAdd()
  .setMatch(myfactory.buildMatch()
    .setExact(MatchField.IN_PORT, OFPort.of(1)) // type-checked matching
    .setExact(MatchField.ETH_TYPE, EthType.IPv4))
    .build()) // immutable Match object
  .setActions(actions)
  .setOutPort(OFPort.of(2))
  .setBufferId(OFBufferId.NO_BUFFER)
  .build(); // immutable OFFlowMod; no lengths to set; no wildcards to set
sw.write(flow);

Some of the concepts above will be discussed further below, but the major items to note are the use of the builder design pattern for ease-of-use and the production of immutable objects, the use of objects instead of raw types to enforce type-safe coding and to produce more readable code, built-in wildcarding, and finally there is no need to deal with message lengths.

All switches that connect to Floodlight contain a factory for the version of OpenFlow the switch speaks. There can be multiple switches, all speaking different versions of OpenFlow, where the controller handles the low-level protocol differences behind the scenes. From the perspective of modules and application developers, the switch is simply exposed as an IOFSwitch, which has the function getOFFactory() to return the OpenFlowJ-Loxi factory appropriate for the OpenFlow version the switch is speaking. Once you have the correct factory, you can create OpenFlow types and concepts through the common API OpenFlowJ-Loxi exposes.

As such, you do not need to switch APIs when composing your FlowMods and other types. Let’s say you wish to build a FlowMod and send it to a switch. Each switch known to the OFSwitchManager has a reference to an OpenFlow factory of the same version negotiated in the initial handshake between the switch and the controller. Simply reference the factory from your switch, create the builder, build the FlowMod, and write it to the switch. The same API is exposed for the construction of all OpenFlow objects, regardless of the OpenFlow version. You will however need to know what you are allowed to do for each OpenFlow version; otherwise, if you for example tell an OpenFlow 1.0 switch to perform some action such as add a Group, which is not supported for it’s OpenFlow version, the OpenFlowJ-Loxi library will kindly inform you with an UnsupportedOperationException.

There are some other subtle changes introduced, for the better. For example, many common types such as switch datapath IDs, OpenFlow ports, and IP and MAC addresses are defined by the OpenFlowJ-Loxi library through the DatapathId, OFPort, IPv4Address/IPv6Address, and MacAddress, respectively. You are encouraged to explore org.projectfloodlight.openflow.types, where you will find a wide variety of common types that are now conveniently defined in a single location. Like the objects produced from builders above, all types are immutable.

For more information on how to use the new APIs exposed in Floodlight v1.0, please refer to the OpenFlowJ-Loxi documentation and examples.

There are many more minor details, which can be found in the release notes. I have been grateful to have the support of many Floodlight developers, and together we have worked to provide the highest quality release within a reasonable time frame. I would especially like to thank the following individuals and beta testers for their code contributions, debugging efforts, and assistance throughout the development and release process:

Rui Cardoso
Hung-Wei Chiu
Rich Lane
Qingxiang Lin
Sanjivini Naikar
Jason Paraga
Naveen Sampath
Rob Sherwood
Sebastian Szwaczyk
KC Wang
Andreas Wundsam

Based on further community feedback, there will be minor releases to address any issues found or enhancements anyone would like to contribute. The mailing list has seen quite an uptick in activity over the last few months (minus the holiday season =) ), and I look forward to seeing all the novel and innovative ways people find to use Floodlight v1.0!

If at any time you have a question or concern, please reach out to us. We rely on our fellow developers to make the most effective improvements and find any bugs. Thank you all for the support and I hope you find your work with Floodlight v1.0 fun and productive!

Floodlight v1.0 can be found on GitHub at:

http://github.com/floodlight/floodlight/tree/v1.0
Any updates leading up to a minor release after v1.0 will be placed in master at:
http://github.com/floodlight/floodlight
And finally all “bleeding edge” updates will be in my repository’s master branch at:

http://github.com/rizard/floodlight

If you need an older version of Floodlight for any reason, they can still be found on GitHub.
Floodlight v0.91 (old master) can be found at:

http://github.com/floodlight/floodlight/tree/v0.91
Floodlight v0.90 can be found at:

http://github.com/floodlight/floodlight/tree/v0.90

The download sites openflowhub.org and bigswitch.com will be updated as soon as possible and in the near future.

Lastly, I’ll leave you with a short list of to-dos for upcoming minor releases. These are items I would have liked to have incorporated into v1.0 but did not fit within the release timeframe. If anyone is interested in exploring these avenues of development and contribution, please feel free to ask and I can provide you with the details. All other suggestions are welcome as well!

  • Modify the Static Flow Pusher to check flow validity before inserting flows into storage. This will allow a detailed, root-cause error message to be sent back to the user via the REST API.
  • Add handshake handlers for OpenFlow 1.1, 1.2, and 1.4. OpenFlow 1.1, 1.2, and 1.4 concepts and types are supported by the controller; however, the initial handshakes have not been completed yet.
  • Find and fix a very rare bug (only seen twice in 6 months) that causes an OpenFlow 1.0 factory to be used with an OpenFlow 1.3 switch upon initial handshake. This will cause an exception to be thrown. I have noticed it when the switch is under high load and has many unmatched packets about to be sent as OFPacketIns after the handshake completes.
  • Modify Loxigen to force OFMessage and all classes that extend it to not use the XID field in their equals() functions. This bug prevents comparing the content of an OFMessage without explicitly comparing each field of the OFMessage minus the XID (and the content varies per OpenFlow version and per OFMessage type). This bug is presently impacting the OFMessageDamper; the details of this issue are included here.
  • We do not have a VM yet that contains Floodlight v1.0 and an updated OVS. You should download Floodlight directly from GitHub.
  • Create a “compatibility layer” that allows all pre-v1.0 custom modules work seamlessly within Floodlight v1.0.
Happy coding!

Ryan Izard
ECE Department, Clemson University
rizard@g.clemson.edu
Big Switch Networks
ryan.izard@bigswitch.com

Erlang Solutions and InfoBlox Release an OpenFlow 1.2 Switch

Kudos to the folks at Erland Solutions and InfoBlox.  Today, they released an OpenFlow 1.2 compliant switch, code-named LINC, which as you might have guessed is written in Erlang.  The switch is offered under a the commercially friendly Apache 2.0 just like the Floodlight OpenFlow controller.  Erlang Solutions plans to offer professional services around the LINC switch and OpenFlow in general, including set-up, configuration, support and testing.

LINC is available at flowforwarding.org. Check out the video of it in action.

As a member of the Floodlight team, I’m really excited to see future versions of OpenFlow begin appear in switch designs and we are also hard at work in bringing Floodlight (which currently supports OpenFlow 1.0) up to speed with these designs as well.

– Mike Cohen

An OpenFlow Programmable Patch Panel

Kudos to Dan Hersey, a systems engineer at Big Switch Networks, who recently set up a programmable patch panel using OpenFlow.  Its a creative and very useful way of taking advantage of open source tools like Floodlight and Indigo. He even went all the way and wrote an IPhone app that can push static flows to help manage the patch panel he built.  Awesome! Dan’s Article follows below.

When I started exploring the OpenFlow protocol I was struck by how fundamentally it could change networking.  OpenFlow truly provides a clean slate to correct the network mess we have created over the last 20 years. Solutions such as network virtualization, lawful intercept, network service insertion and other super cool (and highly desirable) concepts based on OpenFlow have garnered the most press but there is limitless possibilities.

Continue reading »

Google, SDN, and Open Source

Last week, Google made a huge announcement in the world of software-defined networking.  They had in fact built their own OpenFlow-based SDN (including their own custom networking gear) and were using it to manage all of their production WAN traffic.  Google’s SDN enabled it to implement a global bandwidth management and traffic engineering system, saving money on bandwidth and hardware.  

For a company very secretive of its infrastructure, Google took a major step in support of the growing OpenFlow and SDN ecosystems.  They immediately dispelled any myths and concerns about the maturity of SDN  and made it clear that real, reliable software-defined networks were managing production traffic in one of the most complex infrastructure environments in the world.  This is a huge boost to the SDN ecosystem. Continue reading »

Indigo 2012.03.19 Released!

The Indigo team is pleased to announce release 2012.03.19.

For those not familiar with Indigo, its an open source project that supports OpenFlow on a range of physical switches (including Pronto and Netgear).  Indigo firmware is actively used in many campus deployments (at Stanford and several other schools), in at least one OpenFlow startup, a 20-switch conference network deployment and a 32-switch data center deployment.

If you want to get your hands dirty with OpenFlow, Indigo on a platform like Pronto is a great way to do it.  And of course, its well tested with the Floodlight controller. Continue reading »

Free t-shirts for Floodlight developers!

We’ve gotten our first stock of Floodlight t-shirts in and I’d love to share them with folks developing applications on top of Floodlight (they are really nice microfiber!).  As I’m sure you know, Floodlight is our Apache-licensed OpenFlow controller platform.
There are just a few guidelines:
  • The “application” is up to you but it must be more interesting than a simple hello world-style app.  Some of the work done on Trema apps (https://github.com/trema/apps) is probably a good guide here.  Be creative and think about some interesting ways to use OpenFlow.  We will be liberal on this front but if you have a question or need ideas, just ask.  
  • The application must be open source.  We will include it in the Floodlight repository as a code example if its not hosted somewhere else already.
  • The application can either be in Java using Floodlight’s event handlers or written to use the static flow pusher REST API in any language you choose.
The submission process is simple — just email the Floodlight admin list (floodlight-admin@openflowhub.org) and let us know what you’ve built (or are in the process of building).   We’ll take a look and send you a free t-shirt!