To control access to MSMQ objects, MSMQ computers must log on to a Windows NT Server domain. If you choose not to use access control, MSMQ dependent clients, independent clients, and servers need not log on to a Windows NT Sever domain.
For more information on Windows NT domain trusts and their impact on MSMQ installations, see "Windows NT Domain Considerations" in Chapter 5, "Securing Your MSMQ Enterprise."