What is a Transport Provider

A transport provider is a dynamic-link library (DLL) which acts as an intermediary between the MAPI subsystem and one or more underlying messaging systems. A messaging system is some specific mechanism by which messages are sent and received. Some examples of messaging systems are:

• A shared network file system that the transport provider writes messages to directly.
• A TCP/IP network interface that the transport provider uses to connect to a messaging server.
• An online service that users dial into.
• A host-based messaging or office automation system.
• A set of remote procedure calls to a messaging server.
• Anything that can be used to transfer data from one computer to another.

A transport provider DLL must conform to the interface specified by MAPI. As a transport provider developer, you will implement this interface in terms of the functionality present in the messaging system.