What about COM?

So then, should you always use message queuing for communication between applications? This isn't the case either. If your business environment requires some activities be carried out synchronously, then a communication method such as DCOM or CORBA is better suited to perform this type of processing. If everybody using the application is always connected to the LAN, and all of the application servers are connected over fast, local, reliable links, then messaging may not necessarily be the best answer either. And for many developers, message queuing is a new and unfamiliar technology that they may not be willing to make an investment in.

A few short guidelines of when to use message queuing can help to clarify the decision to use it or not:

• If the application you are communicating with is not running at the same time as your application, use message queuing.
  
  
• If the message is important and will cause problems if it is lost, use message queuing
  
  
• If your application is not always connected to receiver application, but still needs to be functional, use message queuing.
  
  
• If your application cannot maintain a reliable network connection to the receiver application, use message queuing.
  
  
• And if you perform many communication tasks with other applications asynchronously, and may or may not care about their response, use message queuing

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