Data Control Receiver Sender Receiver

Massively parallel multicomputers require a high-performance interconnection network. The physical channels which connect nodes in the network are the components that most commonly impose restrictions on the amount of data which can be communicated between nodes of the network. Several di erent schemes for maximizing the bandwidth of physical interconnection channels are examined. Conventional technology centers on 5V electrical signalling. Within this paradigm, there are several di erent methods of maximizing throughput of a channel, given its limited bandwidth. Simplex and duplex channels are examined, as well as arbitration protocols and transmission line pipelining. Non-conventional technologies which achieve higher bandwidth transmission through low-voltage signalling and ber optic communication are also examined. For the present, it is expected that most networks will continue to use electrical signalling with low-voltage signalling because ber optic hardware is too expensive. As technology changes, though, it may become more common for networks to be built out of optical or other new technologies.