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With this scenario, any application that produces data to be shared has a method to communicate with those that wish to consume it.
Different Message Channel Implementations
Fixed set of channels
One implementation variation is that the set of Message Channels available to an application will tend to be static and fixed. Therefore, when designing an application, a developer has to know where to put what types of data to share that data with other applications, and likewise where to look for what types of data coming from other applications.
It is understood that these communication routes cannot be created dynamically and discovered at runtime. They will need to be agreed upon during application design to allow each application to understand where its data is coming from and where the data is going.
Unidirectional channels
Another implementation decision is whether our channels will be defined as unidirectional or bidirectional. Actually, it’s neither; a channel really like a container that some applications add data to and other applications retrieve data from.
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