The evolution of the system x control architecture

The existing control of System X is based upon a number of processor clusters, supporting message passing software. Each cluster is a shared memory multiprocessor, and they are linked by a serial mesh network. The paper shows the stage by stage evolution of this control architecture. The mesh network is replaced by an FDDI optical LAN, providing an open interface to which heterogeneous processors may be attached. It also provides a point of attachment for a new processing platform. This platform is based on a loosely coupled network of RISC micro processors, and allows open ended expansion of throughput and storage. It supports an object oriented software style, which grows naturally from the message passing software base. The target of this evolution is an open network control architecture, which will allow the system to play many roles in the networks of the 1990s.