This may be hard to believe, but OpenFlow is now about four years old, and late last year version 1.4 of OpenFlow was unveiled. This week, startup Pica8 became the first vendor to support 1.4, which may be the first OpenFlow version that’s ready for prime time. OpenFlow features a number of new features, improvements, and one change.
The new features are:
- Bundles. The bundles feature of OpenFlow 1.4 enables a group of OpenFlow messages to be “bundled” as a single, which allows for better synchronization of changes across as series of switches. This is similar to a “commit” of multiple configuration changes in traditional layer 2/3 environments.
- Optical ports. In 1.4, support for Optical ports has been added. OpenFlow can now be used to configure or monitor optical ports, which brings FiberChannel over Ethernet into, play in an SDN. This also allows for higher-speed transmission rates to be used in the SDN.
- Synchronized tables. Flow tables can now be synchronized uni-directionally or bi-directionally. This has some implications on the way data flows are synchronized to transmissions of data. This effectively doubles the TCAM scalability of the switch.
The change to the protocol is that the default port is now TCP 6653 from 6633 and 976. Customers should discontinue the use of these ports.
- Flow removed reason for meter delete. This adds another way to remove flow entries from flow tables.
- Improvements in multi-controller functionality. Multi-controller has been available since version1.2, which can increase the throughput of the control layer. OpenFlow 1.4 brings new features to improve the synchronization of the controllers.
- Eviction and vacancy events. In previous versions of OpenFlow, new flow entries create errors and are dropped when a flow table is full. The eviction feature enables the switch to drop entries that are of low importance. Vacancy events enable the controller to be notified when a capacity threshold is reached on TCAM capacity.
- New error codes. There were a number of error codes added to better inform the controller of duplicate instructions and avoid problems and other factors. There are too many error codes to list here, but they’re all in the specification.
The new features in 1.4 focus on the control layer and make OpenFlow stable and resilient enough for mainstream data centers. Also, in a multi-controller deployment, controllers can be synchronized based on a number of factors, including flow monitoring and change notifications. Pica8 has added most of these features and combined them with their operating system, PicOS, to create a highly flexible set of switches. The new features allow Pica8 to move more towards an OpenFlow-based "fabric," rather than a collection of point product switches. The company’s ability to add OpenFlow 1.4 support rapidly shows the flexibility of its software-only solution and Linux-based programmable OS.
IT departments that have been testing OpenFlow-based platforms should take a look at the 1.4 products, such as Pica8, as it seems like OpenFlow has finally matured.