OpenFlow is a new open source project borne of a six-year research collaboration between Stanford University and the University of California at Berkeley. It is a routing protocol that enables software-defined networking, which gives users the power to define flows and paths of traffic through a network, regardless of the underlying hardware. Earlier this year, an industry consortium, Open Networking Foundation (ONF), launched to develop and promote OpenFlow, and it was also the centerpiece of the Interop 2011 tradeshow held in Las Vegas in May.

The consortium includes most of the most powerful industry players. Founding members of the ONF include Deutsche Telekom, Facebook, Google, Microsoft, Verizon and Yahoo; non-founding members include Cisco, Brocade, Juniper Networks, HP, Broadcom, Ciena, Riverbed Technology, Force10, Citrix, Dell, Ericsson, IBM, Marvell, NEC, Netgear, NTT and VMware.

Fifteen vendor participants in the OpenFlow Interop lab were showing beta products. They included Big Switch, Broadcom, Brocade, Citrix, Dell, Extreme Networks, Fulcrum, HP, IBM, Juniper, Marvell, NEC, NetGear and NetOptics. Pronto Systems, a maker of switches that can run OpenFlow software, was also involved, and its products are already shipping.

Yet, there are plenty of naysayers about OpenFlow as well, including (not surprisingly) Juniper, a company that has promised eventual support, but has been ho-hum about the new protocol overall.

We've put together a comprehensive, easy-to-read PDF guide on OpenFlow collected from Network World's coverage of the protocol over the past few months. Read and become an instant expert.