Overview

Like all summary chapters in books, this is the one place where you will tend to see what the author really thinks about their subject matter. This chapter is no exception, so if you don't want to be bombarded by my opinions, stop reading here!

Let me start with the good things.

Figure 19.1: Summary of services

The Strengths of DCOM

Visionary There is no doubt that what Microsoft has produced with DCOM is visionary stuff. They have provided middleware an infrastructure for building distributed systems that can be used with components, is accessed using a common interface based on the same component model, and that encompasses a vast range of services.

Integrated This is an enormously powerful concept. It is worth pointing out that no other middleware products on the market are built in this way with all the services a developer may need to build a distributed system integrated within one product and with one interface to access all the services.

All the other vendors provide a particular type of middleware DTPM, RPC, MOM product. If you want to use messaging with distributed transaction processing you usually have to use a MOM product with a DTPM. With DCOM you have no need to do this practically all the services you need are built into DCOM and provided using the same interface.

What this means from the developer's point of view is that he or she only has to learn one product and one approach. After mastering the concepts in...