Chapter 7 - Message Queuing Using MSMQ

Abstract

This chapter shows how Microsoft Message Queue (MSMQ) uses queues to store messages that provide a communications mechanism between applications. MSMQ provides solutions to a range of problem scenarios that appear during application development. It gives options that are available for the usage of queues and the variety of ways in which messages are created, sent, and received. A common example is in client-server architecture where a direct connection to the server is needed to handle information updates. In this situation, any disruption to the server causes all client applications to fail, possibly causing idle staff, and lost productivity. Such a disruption may be caused by a hardware failure, power outage, or a server upgrade. The solution is to use message queuing to “uncouple” the client and the server by providing a storage point for communication between them. If a connection to the server cannot be made, the data entered in the client application can be stored in a client-side message queue. Once a connection is reestablished, the messages are then automatically forwarded to the destination queue on a remote server. Then, an application on the server reads the messages from the message queue and performs the necessary database updates. MSMQ also provides the plumbing needed for true distributed processing.