As for a large-scale Lync telephony deployment requiring access to a lot of hardware, this, too, can be true for some deployments. Microsoft says a typical small-scale deployment will use up to three servers while the company's large-scale reference architecture uses 14 servers. However, these do not need to be dedicated machines. Lync's servers can be run in virtual machines, Microsoft says, including Hyper-V, VMware and any other Microsoft-certified hypervisor. (Reference materials are available .)

Morimoto points out that Lync in the SMB market can be rolled out with as few as two servers. The need for separate servers "depends on scale," he says. "For your minimum configuration where you're doing in-house instant messaging, Web conferencing, external IM/Web conferencing, your minimum buy is two servers. You have to have an internal server and a server on the edge. They can be virtualized. In our environment I have three servers running Lync. I have one internal server running IM/Webconf, an edge server and a voice server -- all virtualized."

If a customer runs Lync Standard Edition, "they need three servers total, two of which are optional: an edge server (optional, which is in the DMZ, and enables remote access) and the XMPP Gateway (which is optional), and Standard Edition Server (everything else)," says Microsoft.

Microsoft says that an enterprise can use a setup similar to Convergent Computing's: one or more edge servers in the DMZ (although Microsoft says this separate server is optional), back end servers (SQL databases) and front end servers (for almost all the other features or "roles" that Lync offers).

But here's the catch: With the Enterprise Edition, only some of Lync's features, called "server roles," can be colocated on the same physical servers (reference architecture is ). According to Microsoft, many specific server roles "must each be deployed on a separate computer." This includes Director, Edge Server, Trusted Application Server, Group Chat and others. Using Microsoft's reference architecture of 14 servers, Lync can support "upwards of 80,000 users," Microsoft says.