Cisco's acquisition of WebEx is in many ways as startling as if Alcoa had bought an aluminum canoe company. Cisco makes network gear, and WebEx is a consumer of network technology. The apparent disconnect has created all kinds of speculation on the motivation behind the deal, and the big question is whether WebEx is an indicator, or even a driver, of a major change in the Cisco model - and if so, to what?

One popular theory is that Cisco is "taking on Microsoft." The conclusive point to debunk this theory is that Cisco's sales force doesn't call on the customers that would be buyers of enterprise collaboration and application software tools. The same argument can be applied to the "Cisco is taking on IBM" theory. It's clear from the ultracautious positioning of Cisco's Service Oriented Network Architecture (SONA) that the company hasn't wanted to step on the toes of any of the big IT/software companies. Why start now?

Another theory is that Cisco wants to get in on the Google model. Does this mean WebEx and Google are supposed to be leveraging the Internet model? According to WebEx's site, the company has a "dedicated private global network" it calls MediaTone, and the "Internet provides only the first mile/last mile" connection. WebEx's latest quarterly revenues were about 1% of Cisco's, so small they would be less than rounding errors in the numbers, which isn't enough to change Cisco's model.

If all the hype on the deal is wrong, why did Cisco do it? The popular buzz grazed the real issues but didn't hit them squarely, so let's take a deeper look.

Cisco is not taking on Microsoft; Cisco is defending against Microsoft possibly taking on Cisco. The service-oriented architecture (SOA) wave is a major problem for Cisco and other enterprise network players, because it threatens to suck differentiating features, such as security and application management, out of the network and into the IT software tools. It's been hard for Cisco to counter what is clearly an application software trend, so it's settled on the idea of ceding SOA to the IBMs and Microsofts of the world, and keeping another application - collaboration - for itself. But Microsoft and IBM also are nibbling at what they call unified communications, which is threatening Cisco's collaboration strategy. And WebEx is all about collaboration.