SQL Server 2005 Service Broker (SSB) is an asynchronous messaging technology built into SQL Server. With SSB, you essentially get the power of messaging technologies like Microsoft Message Queue (MSMQ) combined with the relational database capabilities of SQL Server, all controlled with Transact SQL statements.
However, because SSB ships only with SQL Server 2005, harnessing its power with other technologies such as SQL Server 2000 may be a bit of a mystery to you. You could get a third technology such as BizTalk involved to link the technologies. Maybe an alternative called external activation is the way to go, but SQL Server Books Online doesn't provide a clear way to implement external activation and it's complicated besides.
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