Physical Channel Restrictions

When using physical channels, take care that enough WIREs are available for all the inter-processor connections required. Each WIRE can support only two physical channels, one in each direction. If two processors need to communicate over a physical channel, they must be directly connected by at least one physical wire. Restrictions on Network Configuration and Restrictions on Physical Channels describe in detail the restrictions on the use of physical channels. Some restrictions on the use of virtual channels are also described there. These can usually be ignored in networks that use only virtual channels, but become more important when physical channels compete for the available wires.