1. An apparatus for performing message passing decoding operations, the apparatus comprising: memory including a set of memory locations for storing L sets of Z K-bit messages, where Z is a positive integer greater than one and K and L are non-zero positive integers; a node processor including a plurality of node processing units, each node processing unit for performing at least one of a constraint node processing operation and a variable node processing operation; and a switching device coupled to the memory and to the node processing unit, the switching device for passing sets of Z K-bit messages between said memory and said node processor and for reordering the messages in at least one of said sets of messages in response to switch control information.