Streams

Streams apply to IBM® WebSphere MQ Version 6.0 queue managers only, and provide a way of separating the flow of information for different topics. A stream is implemented as a set of queues, one at each broker that supports the stream. Each queue has the same name (the name of the stream). The default stream set up between all the brokers in a network is called SYSTEM.BROKER.DEFAULT.STREAM.

Streams can be created by an application or by the administrator. Stream names are case-sensitive, and stream queues must be local queues (not alias queues). Stream names beginning with the characters 'SYSTEM.BROKER.' are reserved for IBM WebSphere MQ use.

A broker has a separate thread for each stream that it supports. If multiple streams are used, the broker can process publications arriving at different stream queues in parallel. Streams can also provide high-level grouping of topics, can restrict the range of publications and subscriptions that a broker has to deal with, can provide access control, can define a certain quality of service for broker-to-broker communication of publications, and can allow different queue attributes to be assigned for publication on different streams.