A fuzzy algorithm for priority estimation in Immediate Area Networks

Abstract The advent of lower cost computers has accelerated the use of distributed computer networks. These systems vary in architecture from those that are tightly coupled by extensive parallel buses or shared resources, such as memory, to those that are loosely coupled and connected by long buses, which are usually serial in nature. Both of these extremes serve their particular applications well, but a middle ground exists where neither of the techniques quite satisfies the requirements. Situations exist where the processors may be in close proximity to each other but still have the requirement for high transmission speeds and the flexibility and modularity of a loosely coupled network. The proposed architecture for an Immediate Area Network (IAN), which falls into this category, is discussed in this paper. In an application of this nature, the importance or priority of the message may be a significant factor. In those cases, it is necessary that the high-priority messages be delayed as little as possible before transmission. We may also expect very heavy loads on the bus where bursts of messages far exceed the capacity of the bus for a time. During such bursts, messages may be delayed for extended periods while multiple collisions and back-off delays occur. A protocol algorithm for back-off determination is presented to minimize the delay of high-priority messages.