Deflection routing

Deflection routing is a routing strategy for packet-switched networks which does not require buffering of packets. Every packet has preferred outputs along which it wants to leave the router, and when possible a packet is sent along one of these outputs. However, two or more packets may want to leave along the same output (which is referred to as a contention among packets), and then only one of the packets may be sent along the link, while the others are sent along available outputs, even though the other links are not preferred by the packets (because, for instance, those links do not yield shortest paths).