VMWare CTO and co-inventor of OpenFlow, Martin Casado, played down the rivalry between VMware and Cisco at a cloud conference in California last week.

Critics have suggested that the two Silicon Valley tech giants are competing with each other more and more as the bridge between hardware and software narrows.

“Everyone loves a David and Goliath story,” said Casado at the Cloud Innovation conference in Saratoga last Thursday. “The reality is, Cisco builds physical gear...and we build software at the edge...and there’s no reason why there isn’t this great joint world together.

“Seventy percent of our deployments have Cisco physical infrastructure.”

Casado, who sold his network virtualisation start-up to VMware for $1.26 billion in 2012, admitted there are some areas of overlap between the two businesses but claimed they are incredibly small.

“Many of the deals we’ve sold lately are based on functionality that Cisco could never do in an ASIC,” he said. “It’s stuff that’s done in software on the edge with the aid of a hypervisor.”

Casado's said his latest work for VMware has focused on improving private cloud security for enterprises. 

"We've been developing this concept called the Goldilocks zone, which is a corollary to network virtualisation, but taking advantage of the hypervisor," he said.