Combinatorial systematic switch codes

Multiport switches are commonly used as data processing and routing devices in computer networks. A network switch routes data packets between its multiple input and output ports. Packets from input ports are stored upon arrival in a switch fabric comprising multiple memory banks. This can lead to memory contention when distinct output ports request packets from the same memory bank, resulting in a degraded switching bandwidth. To solve this problem, switch codes are introduced by Wang et al. [1] as a tradeoff between redundancy and service. Using techniques from combinatorial design theory, we improve their result on switch codes serving any one-burst request to a denser set of parameters. New constructions for switch codes serving repetition limited request and consecutive-generation request are also given.