VMware's Nicira Emphasizing Virtual Switches Over OpenFlow for SDN
Analysts at IDC said in a Dec. 19 report that SDN revenues will hit $360 million in 2013, and reach $3.7 billion by 2016. "SDN's ability to decouple network logic and policies from the underlying network equipment allows for a more programmable network," Rohit Mehra, vice president of network infrastructure at IDC, said in a statement. "Providing better alignment with the underlying applications, this programmability allows for greater levels of flexibility, innovation, and control in the network. Logic and policies that can be defined, changed and modified result in a more dynamic network, providing the scale network administrators so desperately crave."“The problem is, we actually got it wrong,” he said. Looking at VMware’s virtualization platform, Nicira officials realized that the first piece of network intelligence was in the hypervisor of the virtualization technology that had changed the way servers were used. VMware’s platform included vSwitch—essentially virtual switches in the hypervisors, which already were at the edge of the network. Seeing that, the need for OpenFlow to control switches was greatly reduced, Casado said. Virtual switches already were at the edge of the network and on the servers themselves, and they run on the common—and flexible—x86 architecture. They didn’t require any new algorithm in a proprietary ASIC chip, and the “level of visibility you have is like a networking [administrator’s] dream." “We had this ‘aha’ moment,” Casado said during the whiteboard session, noting that Nicira officials, during the first year of the company’s existence, “realized that something really important was happening” with virtualization technology. OpenFlow still has some uses, particularly in directing traffic across the network, he said. But all the other functions—from quality of service, billing and inventory to service-level agreements (SLAs), security and network isolation—can be controlled via virtual switches. Through its Network Virtualization Platform (NVP), Nicira has created a virtual network overlay that is managed by a controller system that essentially takes the physical network and creates a virtual pool of network capacity that is easy to program and to manage, and can create tens of thousands of isolated virtual networks to meet the demands of disparate and dynamic workloads. It includes the Open vSwitch—software in the server hypervisor that offers remote network control—that can work with existing XenServer, Xen, KVM or VMware ESX hypervisors, or as an NVP Gateway in a virtual or physical appliance. Casado said Nicira next year will release a controller that will integrate into the hypervisor that will be vendor-agnostic and hypervisor-neutral, and work with any cloud management platform. One version will be integrated into VMware’s platform, working with such solutions as vCloud Director, ESX and vSphere, and another that will work with other hypervisors and cloud platforms, such as XenServer and OpenStack, he said.
Nicira’s Casado said that while at Stanford, he created OpenFlow to take the networking intelligence found in expensive, complex switches and put it into a software controller—a “brain” to control everything in the network. This way, network could be more dynamic, flexible and responsive to the needs of the applications and services in the data center. A wide range of vendors—from established players like Cisco Systems and Hewlett-Packard to startups like Big Switch Networks—have embraced OpenFlow in their SDN solutions.