Coming soon: Windows XP Service Pack 3 featuring, network access protection, which is Microsoft's answer to NAC.

It’s been a long time coming. Microsoft initially issued the NAP client for XP last year, then reissued it a few months later with some upgrades, then promised the final version with SP3, which seemed delayed and delayed and delayed.

With its arrival, users of XP - apparently very loyal and in some cases unwilling to switch to Vista - who adopt Windows Server 2008 will be able to deploy NAP using the NAP endpoint-reporting software. The upside is that it eliminates some of the client-deployment issues that discourages many who are considering this form of NAC.

Had the NAP upgrade to XP come out earlier, XP users could have deployed NAC that is in compliance with informal standards that make it possible to blend NAP elements with NAC elements to produce endpoint checking. Server 2008 would not have been a necessary element in such a deployment.

Even so, whenever Microsoft does release XP SP3 it will still be possible to implement a multivendor NAC deployment that doesn’t rely on Server 2008 as the policy server.

SP3 adds many other improvements that customers have been clamoring for, so it attracts much more than NAP-only interest.

Overall, SP3 will extend the life of XP for a significant number of customers and as part of that may prove useful to that segment looking to deploy NAC without having to distribute a separate client for it.

Tim Greene is senior editor at Network World.