Switching networks for Transputer links

The simplest, and in many ways the ideal way of thinking of a totally reconfigurable machine made from transputers, is to imagine all their links being connected into one big switch. To make any arbitrary network in a non-blocking manner this switch would have to have the function of a 4T×4T crossbar switch. However since the transputer links only support one-to-one connections, this switch could be thought of as a set of 4T 4T-to-1 multiplexers. This ideal arrangement is prohibitively expensive for all other than modest numbers of transputers. The paper examines how to construct universal switching networks for many hundreds of transputers