This page contains a complete reference to Rabbit MQ's implementaton of version 0-9-1 of the AMQP specification.
The original specification was published by the AMQP WG in 2008 and is made available under the AMQP license.
This is a simple flow-control mechanism that a peer can use to avoid overflowing its queues or otherwise finding itself receiving more messages than it can process. Each exchange belongs to one of a set of exchange types implemented by the server.
Note that this method is not intended for window control. The exchange types define the functionality of the exchange - i.e. It is not valid or meaningful to attempt to change the type of an existing exchange.
Durable exchanges remain active when a server restarts.