Currently, the biggest embracers of OpenFlow in the industry seem to be the data centres. Some university campuses and labs are also using it. The OpenFlow specification itself is, well, “open”. In its essence, OpenFlow is a means of setting up the datapath in a network element (switch, router, etc) from a controller, which is outside the network element. In the WLAN world, the CAPWAP protocol is meant to do the same thing, but it is specific to network elements which are wifi access points.
The model is the same OpenFlow mode—a WLAN controller (or CAPWAP controller) sends messages to wifi access points about what datapaths they set up, what firmware to use, when to change the firmware, control the radio power, etc. OpenFlow does not yet define the specifics for WLAN or the equivalent of the fields and attributes in the CAPWAP messages. But it does seem natural and simple to add more types in the OpenFlow messages to cover what the CAPWAP protocol tries to do.
In the industry, somehow the number of sources for CAPWAP implementation has been nowhere what we have seen for other control planes like LTE, GSM, Ethernet switching, routing, MPLS, etc. This is yet another motivation for a push to use OpenFlow for the purpose of controlling wifi access points.
Rajesh Kumar Sundararajan focuses on routing and switching solutions for broadband networks and service delivery platforms. He has over 16 years of industry experience in strategising, managing and developing products and business models for communications and network applications across multiple technologies which include ATM, LAN switching, MPLS, Carrier and Metro Ethernet. He holds a bachelor’s in electrical engineering from Bangalore University, India and a master’s in telecommunications systems engineering from the Indian Institute of Technology, Kharagpur, India.
With the Broadband World Forum 2012 less than a month away there is still time to register your interest in the show taking place on the 16 – 18 October 2012 at the RAI Exhibition and Convention Centre, Amsterdam.