A transport class is MVS's way of enabling you to associate one or more XCF groups (based on similar signaling requirements) and then assign them signaling resources (signaling paths and message buffers). A transport class allows you to segregate message traffic according to the needs of an application's group, the lengths of its messages, or both.

For example, you can define a transport class that dedicates signaling resources to a particular application, such as global resource serialization (the SYSGRS group). This would ensure the signaling performance of the SYSGRS group because other applications would not compete for signaling resources in that class.