Mark your calendars for a live chat session about NAC hosted by Network World that features Joel Snyder and Richard Stiennon.

These are two of the best informed and articulate experts on NAC that you will find anywhere, and in addition to being educational, this should be entertaining.

The chat is scheduled for Tuesday July 22 from 2 p.m. to 3 p.m. EST. On that day just click here to log in (login begins at 1 p.m. EST, no registration required).

Snyder, who is a perennially popular NAC instructor at Interop, has jumped into NAC with both feet since Microsoft has shipped its version of NAC, claiming that Microsoft’s entry will be the catalyst businesses need to move forward deploying NAC. “The NAP client is just a base,” Snyder said in an earlier chat. “You don't just do everything that Microsoft says, right? They provide a great base and you build on top of that to meet your needs.”

Stiennon - a former Gartner analyst whose declaration that IDS was dead back in 2003 led to his testifying to Congress about whether government was wasting money on the technology - says NAC can do nothing to enhance security. Three reasons:

1. NAC does nothing to stop the malicious user with a clean computer from having their way with your network.
2. A zero-day infection will infect properly configured machines with up-to-date signatures.
3. NAC violates Stiennon's first and only rule of network security, "Thou shall not trust an end point to report its own state."

This showdown should be fun. Don’t miss it.

Snyder is a senior partner with Opus One, a consulting firm in Tucson, AZ, and a member of Network World Lab Alliance.

Stiennon is a security consultant, popular speaker and founder of Seccom Global, a managed security service provider focused on unified threat management. He writes the Stiennon on Security blog for Network World.

Tim Greene is senior editor at Network World.