Software defined networking (SDN) is generating a lot of buzz these days, but the technology will ultimately make itself useful in the enterprise largely because it will save enterprises time in deploying new applications, predicted Martin Casado, chief architect of networking at VMware.
Casado invented the OpenFlow protocol, one of the cornerstone technologies for SDN, and founded SDN company Nicira, which VMware purchased last year for US$1.26 billion. He spoke Wednesday at the Interop 2013 conference in Las Vegas.
"We're really seeing a strong adoption in virtual networking. We're moving away from SDN as a science fiction and we're hitting an inflection point in the adoption of virtual networking across all sectors -- finance, large enterprise, telcos, service providers," Casado said, in an interview.
While pundits have predicted a bright future for SDN -- IDC expects the SDN market to swell to US$3.7 billion by 2016 -- less has been said about why enterprises will feel it is imperative to deploy the technology. Only in the past year has the case for SDN become apparent, Casado argued.
In order to succeed, a new technology must solve a problem, or relieve a bottleneck of some sort, Casado said. He compared the potential rise of SDN to the core technology that originally made VMware a powerhouse.
VMware built its success on x86 server virtualization, and the killer application for that technology turned out to be server consolidation -- organizations found that they could save significant money by virtualizing their servers and aggregating them on fewer machines.
Casado remembers meeting VMware co-founder Mendel Rosenblum shortly after VMware's launch -- they both taught at Stanford University. Casado recalls that Rosenblum was convinced VMware had a great technology, but wasn't yet sure how it would be used. It would take several years for VMware to understand that server virtualization would best be used for server consolidation.
In a similar manner, VMware has come to believe that SDN's killer application will be "reducing the time to provision IT," Casado said.
"While there are operational savings and capital savings, and they can be significant, the reason that people buy into SDN is that they want to reduce the amount of time it takes to deploy an application," Casado said. "Speed is the key."
Most enterprise IT project managers have, at one time or another, felt the frustration of having to wait days, weeks, or even months for their IT departments to provision the resources necessary to run a new application. Cloud computing offers the potential to reduce the time to wait for computational and storage resources, so the networking remains the sole bottleneck to fast deployment, Casado said.
Some of the networking chores involved in setting up a new application include assigning that application an Internet Protocol number or numbers, configuring the firewalls to recognize legitimate traffic going to that application, and setting up a VLAN that will partition off the application from others on the same network. The organization's access control list may need to be updated and a load balancer may have to be added as well. Lastly, all of these changes to the network must be logged.
The OpenFlow protocol, along with supporting SDN technologies, provides a way to decouple the control software from network switches and routers, setting the stage to automate, or at least expedite, many of these tasks.
In a blog entry posted Wednesday, Casado further expounded on the industry shift to SDN.
"In this architecture, software on the edge ... provides functionality that has typically been found in the network," Casado wrote. "As a result, this software is largely decoupled from the underlying physical network and can be run over any general purpose network hardware that provides IP connectivity."
One big, enthusiastic user of OpenFlow is Google. "We've invested in building our own OpenFlow routers and put them in our data centers," said Vint Cerf, during his keynote at the Usenix LISA (Large Installation System Administration) conference in San Diego last December. Cerf is a Google vice president and chief Internet evangelist, as well as the co-creator of the TCP protocol that is part of the Internet backbone.
With OpenFlow "you can do a very good job of managing where the flows go in your underlying transport system, so we are able to get very high percentage of utilization out of a optical fiber network," Cerf said.