.Net Remoting

While Web services are arguably the best way for clients outside of your organization to access components, what about components within your organization? Many companies are building Web services and using them internally. There is nothing wrong with this approach, but it doesn't provide the best performance. If components are created in .NET and the client applications are .NET, you can place components on shared servers and access them via remoting.

Remoting is the .NET technology that replaces DCOM allowing you to communicate between a client application and components in a binary format. As a result, remotable components are faster than Web services. However, creating remotable components is more difficult because you must add additional code to your components. This code isn't much more complicated than its Web service counterpart, but you cannot directly instantiate a remote component. Instead, you must create a host application that instantiates the component and listens for requests. The good news is that this host can be a Windows service, a Windows application, a console application, or anything that can run and hold the object open.

Not only do you have to create a host application, you must also make several decisions about the remotable object, such as which channel to use. .NET supports both HTTP and TCP channels. The HTTP channel actually uses the SOAP protocol to transport messages to and from remotable objects; this means all messages are serialized to XML. The TCP channel uses a binary stream to transport the messages.

.NET is architected in such a way that remotable components can change channels without being recompiled. You can place the channel information in a configuration file and change from TCP to HTTP or vice versa without recompiling the application. Similarly, you can change a configuration file for the client to match the channel that the host is using.