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Microsoft as the Mac Guy

Here's a neat trick: A Microsoft Unified Communications guy gets up on the podium and, referencing those "I'm a Mac/I'm a PC" ads, he positions his product as the Mac. Well, we're here in Vegas where Penn & Teller hold court, as does Lance Burton, a magician who's one of those only-famous-in-Vegas guys. So maybe you can't blame a speaker for trying a little sleight of hand for himself.

Here's a neat trick: A Microsoft Unified Communications guy gets up on the podium and, referencing those "I'm a Mac/I'm a PC" ads, he positions his product as the Mac. Well, we're here in Vegas where Penn & Teller hold court, as does Lance Burton, a magician who's one of those only-famous-in-Vegas guys. So maybe you can't blame a speaker for trying a little sleight of hand for himself.The place was Allan Sulkin's Interop session on Architectures for Converged Networks, and the Microsoft guy was Russell Bennett, lead program manager. The trick was explaining why Microsoft-approved phones don't interoperate fully on other vendors' SIP-compliant systems.

Before I get to Russell's explanation, the dry, factual answer to that question is because the phones use Microsoft's proprietary Real-Time Codec, which is a wideband codec that Microsoft says can deliver better-than-PSTN quality voice, even in the presence of network impairments. Microsoft-based phones and Office Communicator softphone clients can only talk to non-Microsoft endpoints if you have Microsoft's Mediation Server acting as a gateway to transcode to a standard codec like G.711, G.729, etc. That's why vendors who aren't Microsoft tend to look askance at Microsoft's broad claims of interoperability. Microsoft claims that its SIP implementation, for example, complies strictly with the SIP standards--but, the other vendors reply, what good is that if you still need a proprietary codec or a gateway to talk to them?

The situation is further aggravated by the fact that Microsoft has said, essentially, that you may not need to upgrade your network infrastructure to the same degree you'd otherwise do if you didn't have the high-end Microsoft codec. This is your basic endpoint-vs.-network argument, so you know who Microsoft's main adversary is in this debate. And, indeed, it was a Cisco representative, Bryan Tantzen, who raised the issue with Russell Bennett in the Interop session.

Bennett explained that, as Microsoft sees it, "Clearly there's a whole user experience" around real-time communications, adding, "I don't think we could offer that whole experiences from a generic SIP phone," hence the need for the realtime codec.

Now comes the twist. Hearkening to the John Hodgman-vs.-guy-who's-not-John-Hodgman commercials, particularly recent ones relating to Microsoft Vista, Russell Bennett said of the Mac, "It works perfectly together because it's engineered to work perfectly together." Likewise, such a coherently-engineered system is Microsoft's voice implementation, he explained.

On a related topic, Bennett also said Microsoft has a "philosophical difference" with all the other voice vendors on the issue of Call Admission Control. It's been pretty much an undisputed rule that you have to do CAC with IP telephony, such that excessive call loads that might degrade quality of all calls on the network are diverted to alternate paths, usually the PSTN. Microsoft, in contrast, does not insist on CAC, though Russell Bennett adamantly asserted that this doesn't mean Microsoft favors a free-for-all in which all calls fight for resources on IP links.

"It's not as if we allow unlimited calls to traverse the network; we don't," he said. However, he allowed that it would take a long time to explain the details of how Microsoft does handle CAC.

In fairness, the session was winding down. But still, I doubt Microsoft's going to get many takers for anything short of the pretty stringent CAC policies that enterprises have been putting in place with IPT.