MULTI-NODE DATA PROCESSING SYSTEM

A multi-node data processing system is described in which each node (10-13) includes a processor (PROC) and an inter-node switch (INS). In operation, only one INS is active. The active INS is configured to act as a star coupler, receiving messages from any of the nodes and broadcasting each message to all the nodes including the node in which that INS is located. Each non-active INS is configured to route messages from the local processor to the active INS, and to route incoming messages broadcast by the active INS to the local processor. The system can be reconfigured to make a different INS active.