What's more, messages can now be built or retrieved in segments, and MQ can pass messages by reference. Of course, behind the scenes MQ is using the MQ messaging infrastructure to move the messages throughout the enterprise. The broker can redistribute the information to any interested apps. The engine would then make it known that this information was available to anyone who needed it, and any other apps could subscribe to that topic to begin receiving accounts receivable information. The publisher is the information provider.
Publishers supply information about a topic.
They don't need to understand anything about the apps that are interested in the information. The subscriber is the consumer of the information. A publisher specifies a topic when it publishes the information. If a competing vendor lacks financial reserves it may have trouble surviving tougher sales cycles. And those tough sales cycles may well ensue if IBM's entrance into the messaging world confuses things.