"Traditionally, OpenFlow does not do network virtualization," Casado told Network World back in June. "All OpenFlow does is allow you to control switches and it may allow you to run different applications on the switch. But it doesn't provide you the ability to create a virtual network that's topology independent that supports L2 and L3. I don't know of any OpenFlow solution that does this."
Perhaps with the activity around defining an open source standard SDN controller to go up against Cisco and VMware, this gap will be filled.
Jim Duffy has been covering technology for over 25 years, 21 at Network World. He also writes The Cisco Connection blog and can be reached on Twitter @Jim_Duffy.
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