SQL Server Service Broker provides the SQL Server Database Engine native support for messaging and queuing applications. This makes it easier for developers to create sophisticated applications that use the Database Engine components to communicate between disparate databases. Developers can use Service Broker to easily build distributed and reliable applications.
Application developers who use Service Broker can distribute data workloads across several databases without programming complex communication and messaging internals. This reduces development and test work because Service Broker handles the communication paths in the context of a conversation. It also improves performance. For example, front-end databases supporting Web sites can record information and send process intensive tasks to queue in back-end databases. Service Broker ensures that all tasks are managed in the context of transactions to assure reliability and technical consistency.
Service Broker Documentation
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