As most participants at the inaugural Open Networking Summit extolled the virtues of software-defined networking (SDN) and the OpenFlow protocol, others are waiting for key features to emerge before considering it for their networks.
OpenFlow and SDN allow a network to be programmed as if it were a computer, proponents of the technology say. It provides a layer of abstraction between the physical network to the control element, allowing the network to be configured or manipulated through software, which then opens it up to further innovation.
FAQ: What is OpenFlow?
But missing from OpenFlow, some presenters said, is support for IPv6, MAC-in-MAC Provider Backbone Bridging, Q-in-Q VLAN stacking, QoS and traffic shaping capabilities, fault tolerance and scalability. Some said these gaps limit the OpenFlow protocol's, and SDN's, applicability to their networks.
"We're very much looking forward to IPv6," said Stephen Stuart, distinguished engineer at Google. "Current SDN implementations don't speak the standard protocols" such as IPv6, MPLS, IS-IS with TE, RSVP-TE and BGP. "More people would try out OpenFlow and SDN if they spoke standard protocols."
IPv6 will be one of a number of features coming in Version 1.2 of OpenFlow in December, said Dan Pitt, vice chairman of the summit and executive director of the Open Networking Foundation, an organization driving standardization and adoption of OpenFlow and SDN, and a co-sponsor of the summit.
Others said OpenFlow and SDN are more useful to huge data center-driven companies like Google and network operators than they are to the enterprise.
"I completely embrace the disruptive potential but I'm still puzzled on how it will impact the enterprise," said Peter Christy, co-founder of the Internet Research Group, a Los Altos, Calif., consultancy. "The enterprise is the biggest part of the networking market. Building a reliable SDN controller is a challenging task. Customers don't value reproducing the same thing with a new technology. There have been few OF/SDN 'killer' apps so far. SDN is not ready for the enterprise market yet."
Christy spoke during a panel session on opportunities and challenges with OpenFlow and SDN in the market. Others on that panel took issue with his assessment.
SDN will increase network agility and virtualization in the enterprise, and serve as a common control plane for both wired and wireless LAN infrastructures, said Geng Lin, CTO of the networking business at Dell. "We need the hypervisor and the physical network to work together, collaborate, influence each other" through SDN, Lin said.