.NET Brings Changes to COM Architecture

The introduction of the .NET platform marks a major shift in Microsoft’s recommended application architecture, but it has left some customers and vendors confused about the future of the Component Object Model (COM). Although Microsoft’s initial discussion of .NET gave many developers the impression that “COM is dead,” .NET replaces only the lowest-level piece of the COM architecture, the base infrastructure sometimes known as “Classic COM.” The COM+ Services, which are higher-level building-block services, are being enhanced and will continue to be a key component for many applications.

Role of COM and COM+ Services

What many developers commonly refer to as “COM” is actually composed of two separate layers:

COM is Microsoft’s base operating system infrastructure that increases code reuse by allowing developers to organize software into components. It is being replaced by the .NET Framework as the preferred component technology and is now sometimes referred to as “Classic COM” to emphasize its legacy status.