Google's next target: Unified communications

sells to both large companies and consumers, and no service provider is going to want a Google cloud computing service like Google Voice to come along for free and take away paying customers.

So, Cisco's virtual voice in the cloud could give a service provider the ability to tell its own customers, "See, we have our own version of Google Voice, but you can offer it to your customers, complete with Cisco security and no worries about their loss of privacy."

Kerravala has no doubt that virtual voice from Cisco will compete with Google Voice. "Oh, yeah, its gotta be competitive," he said. "Google Voice is really just cloud-based voice, so that's very competitive with Cisco's telco clients."

Those Cisco clients include many of the major voice and data carriers. The market battle between Google and many companies in unified communications may be a quiet one so far, but it is still very much a battle.