[From Microsoft Certified Professional Magazine
SQL Server 2005's new Service Broker (SSB) component integrates asynchronous programming, queuing, and reliable messaging services with the Database Engine.
SSB applications can send and receive messages between service endpoints, such as server instances, databases, and .NET 2.0 clients. The most common message format is a Unicode string containing a well-formed XML document that SSB sends to and retrieves from a pair of message queues as a SQL Server 2005 native XML datatype.
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