The thorniest questions are about security policy definition and enforcement, which is what Symantec and Juniper focus on, Shech said.

Steve Hannah, a Juniper engineer and co-chair of the TNC subgroup within the Trusted Computing Group, said architectures such as UAC, NAP, NAC, and TNC must converge.

Even Microsoft is humming along to that tune. Mark Ashida, general manager of enterprise networking servers at Microsoft, said that his company has already proved NAP interoperability with other 802.1x-compliant network infrastructure providers.

Microsoft will demonstrate NAC policy enforcement with gear from Enteresys, Extreme, Foundry, and Hewlett-Packard at Interop in New York this week, Ashida said. That all makes Cisco more Microsoft's "Mr. Right Now," than "Mr. Right."