To some, the term "network virtualization" might seem like the latest version of "cloud" – a technology that can do it all, evoked by vendors to allow them to sell more products or expand market share. But listening to Martin Casado, CTO of networking at VMware, explain the use cases for network virtualization at Interop-- and seeing the reaction of the audience -- the possibilities seem very real.
VMware is no slouch when it comes to innovative technology, but it owes much of its success in the networking arena to Casado, the man who authored the OpenFlow protocol and founded Nicira, which VMware acquired and used as the basis for its NSX platform.
Casado explained that the industry is getting hung up on the wrong points when it comes to network virtualization: "We in the community have been a little bit confused with this whole discussion around SDN and missed some very important trends." He said he was happy to see so many different products coming to market but indicated that these are just scraping the surface of what could be accomplished.
He stressed that enterprises should be emulating mega data centers, which have modified their operations to do things like load balancing and security as applications, rather than directly in the network. In these data centers, the physical network provides only basic services, such as point-to-point connectivity, packet replication, priority-based QoS, and unified latency. "Data centers that are built this way are by far the most scalable and successful data centers on the planet, full stop," Casado emphasized. "In those data centers, the network does almost nothing."
Casado compared network virtualization's evolution to that of server virtualization, which caught on for mundane jobs such as server consolidation and consolidation but quickly became leveraged for far more advanced use cases. So far, network virtualization has been used in enterprises to improve agility and provisioning time. But this is shifting to broader use cases that will have even more impact on IT and businesses.
On Interop's keynote stage, Casado and VMware CEO Pat Gelsinger spoke about using network virtualization to solve the security issues that plague IT, a topic Casado broached at the RSA Conferencein February. Some of the attendee response to this was an automatic dismissal at VMware's apparent land grab at the security market, but those I spoke to who paid attention to the details found the concept intriguing.
Casado views security as the most emergent use case for network virtualization, predicting, "security will actually cause network virtualization to cross the chasm." In a typical network, if a hacker breaks into a server or networked device, they have access to all shared services. Network virtualization provides a primitive that enforces least privilege, which limits the attack surface.
The other use case Casado recommended for network virtualization was improving network visibility and debugging, which currently operates at the level of "junk computer science." A typical packet trace tells administrators almost nothing after any significant time has lapsed.
"It's a very difficult problem to get a consistent view of a big distributed system like a network. But network virtualization requires you to solve that problem," Casado explained. Virtualization can allows full packet attribution across the global network, which can provide network managers with a wealth of troubleshooting information.
Casado refrained from talking about VMware's plans, or how the company might approach products in these areas. Instead, he focused on the big picture, and had infrastructure practitioners nodding their heads along with him when he said, "The right way to build a data center is the way new data centers are built today. The physical network is just a forwarding fabric."