Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions (Addison-Wesley Signature Series (Fowler))

by Hohpe Gregor

A messaging system is needed to move messages from one computer to another because computers and the networks that connect them are inherently unreliable. Just because one application is ready to send data does not mean that the other application is ready to receive it. Even if both applications are ready, the network may not be working or may fail to transmit the data properly. A messaging system overcomes these limitations by repeatedly trying to transmit the message until it succeeds. Under ideal circumstances, the message is transmitted successfully on the first try, but circumstances are often not ideal.