Cisco's software defined networking strategy is still vague after the company stated last fall that it planned to add the OpenFlow protocol and API to its Nexus switches, and with this week's much anticipated debut of network virtualization start-up Nicira.

And last week, Network Computing ran a story that said Cisco's SDN strategy and implementation may be proprietary and not based on OpenFlow, the open source network programmability technique developed at Stanford and UC Berkeley.

On the heels of this story and Nicira's debut, we asked Cisco for an update and further detail on its SDN strategy and OpenFlow plans. The company was not forthcoming. Cisco e-mailed this statement from Vice President Ram Velaga:

"Cisco has been at the forefront of driving network virtualization and programmability. Cisco's Nexus 1000V software switching platform, for example, has been in production networks since 2009 and we have more than 5000 customers. Cisco has also provided open programmatic interfaces to our operating systems to enable scalable application integration to underlying network infrastructures and access to third-party management and orchestration tools. Cisco will also continue to support industry efforts to develop SDN technologies and related standards. Ultimately, Cisco sees SDN as incremental capability that can be layered onto existing infrastructure to deliver specific functionality."

Obviously, Cisco is not ready to publicly discuss its SDN strategy and implementation plans, with or without OpenFlow. The industry scuttlebutt is that Cisco has the most to lose should an open source SDN implementation like OpenFlow gain widespread acceptance and adoption in the industry. It would take much of the intelligence out of routers and switches and put it in an external controller that can then program routers and switches from any vendor - including Cisco - to direct traffic based on a variety of variables and open up the infrastructure for further innovation.

The pervading belief is that this would commoditize routing and switching hardware and leave it with little more than the ability to perform basic routing and switching. It would not be in Cisco's proprietary interest to allow this to happen to its hardware. Especially when the company is reporting bang up quarters in which it beats Wall Street estimates and jacks its stock price based on its status quo approach in which network configurability is a highly specialized and Cisco-specific - vendor-specific -- undertaking.

Speaking of Cisco's latest quarter, it appears the company is rebounding quite nicely, thank you, from the doldrums of last year, in which thousands of jobs were cut after the company got too fat from too many acquisitions and ill-advised forays into adjacent markets like consumer. At the same time, Cisco's switching business was under pressure from a nettlesome product transition away from older platforms to newer, more cost-effective products with improved price/performance.

In addition to beating Wall Street estimates in Q2 earnings and revenue, Cisco cut $1 billion in expenses a quarter earlier than planned. It also indicated its third quarter would be up 5% to 7%, with a 12% to 17% hike in earnings per share.

A highlight in the second quarter was sales of its Unified Computing System server platform, with revenue up 91% from a year earlier and an accumulated customer count of 10,763. Overall data-center revenue was up 88%.

Sales of UCS should continue to climb - provided the servers don't spontaneously combust. Cisco issued a field notice this week stating that, due to a failure of a MOSFET power transistor, its B440 blade server could overheat and emit a flash that could take out that server and others in the same chassis. Cisco launched a hardware replacement program to mitigate the problem .

So Cisco is hitting stride once again, which makes its hesitancy in articulating or endorsing a strategy that might undermine its proprietary interests somewhat understandable.