1. A system for communicating a packet, the system comprising: means for converting a packet into cells within an input/output interface, each cell specifying a destination physical address corresponding to a first physical partition of a physically-partitionable symmetric multiprocessor; means for transferring each cell through a switch in accordance with the destination address; and means for forming the cells into a reconstructed packet within the first physical partition; and wherein the physically-partitionable symmetric multiprocessor is programmable as a selected one of a first configuration comprising one physical partition and a second configuration comprising a plurality of physical partitions.