Learning DCOM

Chapter 5. Infrastructure

In this chapter:

• Memory

• Transparency

• Concurrency

• Security

While you can actually write complete, functioning server and client components from the material given in the previous chapters, you’ll find them very limited. In order to give you the bare bones, the following considerations have been ignored:

Memory management

Some programs contain complicated, many-layered pointers as function arguments. These require special handling to send their data across a connection.

Location transparency

Objects can locate anywhere in cyberspace. Location transparency allows a single programming model that allows clients anywhere to refer to distributed objects. In COM programming, you know this object reference as an interface pointer, which can be passed to any component in cyberspace.

Multithreading

Multithreaded programming in COM is different from traditional multithreaded programming. To take advantage of multithreading, you need to learn an important concept called apartments.

Security

You haven’t been shown how to restrict access to a service. Security can be configured by an administrator and can also be finely controlled through programming.

These are the sorts of supporting infrastructure that will be discussed in this chapter.

Figure 5-1. COM applications and apartments

Before we delve in to these discussions, we must introduce an important Distributed COM concept called apartments. ...