The virtual network overlay technology called OpenFlow is popping up more and more in my virtual world. OpenFlow is a part of the networking technology baked into XenServer 6 beta 2 "Project Boston." I've just set up a meeting with Big Switch to talk about their OpenFlow. My friends at the Internet Research Group have published a research paper on OpenFlow. And during my recent briefing at Cisco on the Nexus 7000, there was a professional-yet-stifled reaction when I mentioned OpenFlow. Yes, Cisco is on the advisory board, no, there aren't announced plans for implementing the technology.
Software defined networks, of which OpenFlow is an example, seek to accommodate the impact of x86 virtualization on the underlying physical network. Where before networks could be engineered and then frozen in place, now they must accept the fact that workloads can be mobile and may shift location.
Over the next several weeks I'll be talking with OpenFlow experimenters and implementers in the hopes of shedding light on what the issues that IT managers must take into account as they make strategic design decisions for the next 3-5 years.
It's clear that simply designing networks in the manner of "second verse, just like the first" has come to a breaking point. With Cisco, HP, Juniper, Brocade and others releasing various fabrics, to the Gartner report that challenged the presumptive superiority of single vendor networks, to the widescale implementation of virtual switches, networking is undergoing a rapid evolution. Getting a handle on OpenFlow will help network managers stay a couple of steps ahead of this fast changing scene.