The U.S. Army is in the early stages of implementing what will likely be one of the largest implementations of Microsoft's Active Directory technology.

Following a test period, the Army has begun building a directory that will help its system administrators manage user accounts for up to 500,000 Windows PCs. The upgrade will give the Army greater control over its IT resources and help it establish standard software configurations, says Dan Gilbert, senior Active Directory specialist with FC Business Systems, a contractor involved in the project at Fort Huachuca, Ariz.

The Army expects to increase the security of its IT infrastructure in the process. NetPro Computing Inc.'s DirectoryLockdown software will make it possible to isolate a group of user accounts, or domain, if that group should be compromised by an intruder or mishap. "DirectoryLockdown would prevent the damage from propagating beyond a particular domain," says Jonathan Penn, an analyst with Forrester Research. The Army will also use NetPro's DirectoryAnalyzer and DirectoryInsight tools to monitor the health of local directories as they replicate across its network and respond to any problems.

The project is part of a broader initiative to replace remaining Windows NT systems in the Army's U.S. infrastructure with new versions of Windows. Microsoft plans to stop actively supporting Windows NT after Dec. 31. "We've got to move off of those [Windows NT servers] to something that is being supported," says Gilbert.