Editing IBM MQ (section)

===Communication between queue managers===
This relies on a ''channel''. Each queue manager uses one or more channels to send and receive data to other queue managers. A channel is uni-directional; a second channel is required to return data. In a TCP/IP based network, a channel sends or receives data on a specific port.

Channel types:
*'''Sending channel''': has a defined destination and is associated with a specific transmission queue (the mechanism by which messages are queued awaiting transmission on the channel).
*'''Receiving channel''': receives data from any other queue manager with a sending channel of the same name.

When a receiving channel receives a message, it is examined to see which queue manager and queue it is destined for. In the event of a communications failure, MQ can automatically re-establish a connection when the problem is resolved.

The ''listener'' is the application's network interface to the queue manager. The listener detects connections from incoming channels, and manages the connection of the sending channels to the receiving channels. In a TCP/IP network, the listener will "listen" for connections on a specific port.