A protocol structure for high-speed communication over broadbandISDN

Various possibilities for improving the performance of communications protocols and interfaces so that the slow-software-fast-transmission bottleneck can be alleviated are investigated. An architecture that is an alternative to the existing layered architectures is proposed. The novel feature of the proposed architecture is the reduction in the vertical layering; services that correspond to the definitions of layers four to six in the Open Systems Interconnection Reference Model are combined into a single, horizontally structured layer. This approach lends itself more naturally to parallel implementation. Moreover, the delay of a set of processes implemented in parallel is determined by the delay of the longest process, not by the sum of all the process delays, as is the case in a sequential implementation. In the same way, the total throughput need not be limited by the lowest-capacity process, but can be increased by concurrently performing the function on several devices