Functions of DQM
Distributed queue management has these functions:
- Message sending and receiving
- Channel control
- Initialization file
- Data conversion
- Channel exits
Channel definitions associate channel names with transmission queues, communication link identifiers, and channel attributes. Channel definitions are implemented in different ways on different platforms. Message sending and receiving is controlled by programs known as message channel agents (MCAs), which use the channel definitions to start up and control communication.
The MCAs in turn are controlled by DQM itself. The structure is platform dependent, but typically includes listeners and trigger monitors, together with operator commands and panels.
A message channel is a one-way pipe for moving messages from one queue manager to another. Thus a message channel has two end-points, represented by a pair of MCAs. Each end-point has a definition of its end of the message channel. For example, one end would define a sender, the other end a receiver.