In an enterprise that uses Message Channels to connect between two different applications, you must package information as a message. Messages facilitate information transmission from one application to another. In this case, the Message EIP is used as the transfer medium.
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For example, the following code segment illustrates a SOAP message of a typical request that is transformed by the ESB Profile based on its mediation flow, which contains a header and a body. The header holds information about the data being transmitted, its origin, and its destination, and the body holds the actual data.
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