Message broker

[1] Message brokers are a building block of message-oriented middleware (MOM) but are typically not a replacement for traditional middleware like MOM and remote procedure call (RPC).

[4] The primary purpose of a broker is to take incoming messages from applications and perform some action on them.

Message brokers can decouple end-points, meet specific non-functional requirements, and facilitate reuse of intermediary functions.

[3] Additionally, a more scalable multi-hub approach can be used to integrate multiple brokers.

Frequently systems with real-time requirements involve interaction with the real world (robotics, vehicle automation, Software-defined radio, et al.) The Object Management Group Real-time CORBA specification provides a theoretical foundation for predictable communications technologies by levying the following requirements: For the purposes of this specification, "end-to-end predictability" of timeliness in a fixed priority CORBA system is defined to mean: • respecting thread priorities between client and server for resolving resource contention during the processing of CORBA invocations; • bounding the duration of thread priority inversions during end-to-end processing;