In the previous two chapters, we have looked at how to build an Electronic Commerce application using IIS 4.0, Active Server Pages, and Microsoft Transaction Server. In Chapter 15, we introduced a design methodology known as User-Centered Design, and then designed and built the part of the application that allowed a user to log into the system. Chapter 16 showed how to build the parts of the application that allowed the user to browse the content of the electronic store and select items for purchase.
The last step in the application is to take the contents of the user's "shopping basket" and handle the fulfillment processing to complete the order. In this chapter, we will develop that part of the application. To provide a more robust solution for this part of the application, we will introduce a technology known as Message Queues. This technology will allow the application to support different interfaces to multiple users and other systems, some of which may be connected via unreliable communication networks, and may all not be connected at the same time.