In Chapter 10, we began to look at the ways that IIS and ASP can be used to create a new type of client-server applications . By deploying applications in this manner we can help to alleviate some of the problems associated with traditional client-server applications. In the past, you were forced to install the client application logic onto each computer that would access the server. With the web-based model, the client is actually run on the server, with the user interface presentation usually being the only piece sent to the client. This provides for a much wider range of clients, as well as making it easy to update the clients when the application changes.
In the early days of web-based application development, the system was developed using either script-based or custom-written applications that ran on the web server and performed the application functionality. The advent of Active Server Pages from Microsoft allowed the development of script-based applications, which in turn accessed functionality from Component Object Model (COM) objects that ran on the server. This allows the business and data access logic to be encapsulated in high performance components. But at this stage, it was still left to the application developer to handle all of these components.
Now, with IIS 4.0 and Active Server Pages 2.0, we have access to a very powerful facility to perform the management of these server side components. Microsoft Transaction Server provides an environment in which the COM components of an application can be automatically managed by the system. This frees the developer from having to worry about the management of these objects. By putting the system in charge of handling the objects, the use of these components can be optimized to provide a much more scalable and robust solution. The system that will do this is called Microsoft Transaction Server, and we will become quite familiar with it in this chapter, and the case study that follows..
In this chapter, we will look at the features of Microsoft Transaction Server and see how it can be used to support applications developed with IIS and ASP. Specifically, we will examine:
First of all, let's take a look at what transaction processing is.