Lookahead networks by G. JACK LIPOVSKI AMBUJGOYAL and MIROSLAW MALEK

A fail-soft and easily reconfigurable interconnection network is proposed that can function like a bus or like a shift register ring. Its performance as a bus exceeds the performance of an Ethernet, and its performance as a ring is similar to that of a distributed local computer network (DLCN). It can be reconfigured to a sufficient degree to prune out faults or to partition the network into subnetworks that can use possibly different protocols that are the most suitable for the subnetwork. Its multiple-level priority arbitration appears very useful for mixed voice-data networks, to give guaranteed response times to voice packets. Finally, though it functions like a bus or shift register ring, it is physically connected like a tree; so its cost is linear and delay is logarithmic with the number of processors in the network, and it is relatively easy to install in a building by using practices similar to those used in telephone line networks. This paper describes functions of network-level and some data link and physical-level protocols and develops several key mechanisms to achieve ease of diagnosis and fail-softness.