Virtual control channel and its application to the massively parallel computer RWC-1

Global operation and system control are important issues in massively parallel systems. The paper discusses virtual control networks (VCNs), which are substitutes for the current dedicated control networks. First we introduce a new mechanism called Virtual Control Channel (VCC) used to conduct control information over data network links. The network nodes have control finite state machines (CFSMs) and a VCN is composed of CFSMs. The VCC performs the role of a connection wire between CFSMs. The mechanisms are applied to the RWC-1 machine. The simulation results reveal that reduction and broadcasting operations are efficiently executed on VCNs by exploiting the tree structure.