You can gauge the promise of an emerging technology by the reaction of the biggest legacy player potentially threatened by the new arrival. It walks a fine line between jumping in too quickly and sanctioning a nascent movement that may not otherwise get off the ground, and reacting too slowly and losing advantage to fleet-footed upstarts.
Software-defined networking, then, shows great promise, because Cisco last week showed its hand with the introduction of an official SDN architecture called the Cisco Open Network Environment, or Cisco ONE (not to be confused with Sun ONE, the Open Net Environment once popularized by Sun Microsystems).
Another small sign of the SDN promise: If you Google "software defined networking," "OpenFlow" or even "OpenFlow Networking Foundation," the ad that pops up above the search results is sponsored by Cisco. The company, apparently, views SDN as a real threat.
And well it should. In SDNs the control plane is separated from the data plane and network control handed off to servers, diminishing the role/value of the packet-handling equipment (OpenFlow is a new protocol standard for communicating control instructions).
With the ONE architecture, Cisco seems to be stealing a page from Microsoft's "embrace, extend, extinguish" playbook, by, as Jim Duffy reports, "opening up areas above and below the control and forwarding planes addressed by OpenFlow. This allows customers to program the network using a variety of protocols -- not just OpenFlow -- and further customize it according to their usage patterns and deployment models" (see "Cisco fires back with its own SDN").
SDN developments are starting to boil much more quickly than could have been anticipated even six months ago, as Duffy reports in another piece in this issue (see "What are the killer apps for OpenFlow, SDNs?").
Need is being driven by a number of issues, including limitations of VLANs as companies build out private clouds, according to Kyle Forster, co-founder of Big Switch Networks. That sentiment is echoed by Saar Gillai, CTO of HP Networking, who says that SDNs make it easier to build networks where each application "feels like it has its own network."
Why easier? Because SDNs centralize control and eliminate the need to touch hundreds of devices to effect change, the bugaboo that limits network customization today, says Karl May, CEO of Vello Systems, a maker of OpenFlow and SDN cloud switches.
Then there is the promise on the wide-area side. How would you like to increase link utilization from the 30%-40% common today to close to 100%, the level Google reports it is getting with its new SDN/OpenFlow backbone (see Q&A)?
No wonder Cisco is taking SND/OpenFlow seriously. The promise is hard to ignore.