Why This Chapter Matters

With Microsoft Exchange Server 5.5 and earlier, the administration of Exchange Server was independent of the Microsoft Windows NT Server structure. Exchange Server had its own directory, and it was tied to Windows NT only for mailbox authentication purposes. A mailbox was not directly related to a user object in Windows NT and could be associated with any user or security group. In fact, it was common for an NT domain user account to be associated with multiple mailboxes.

Beginning with Microsoft Exchange Server 2000, there is a much tighter integration between Exchange Server and the Windows domain infrastructure, which is based on Active Directory directory service. This is also true in Exchange Server 2003. As a result, the importance of understanding Active Directory as an Exchange administrator cannot be overstated. This chapter introduces you to the concepts behind Active Directory and describes how Exchange Server 2003 integrates with it.