Analysis of transport layer and LLC sublayer performance within a local area network

Results are presented on the performance of the transport layer and the logical link control (LLC) sublayer within a local area network. The time delays introduced by each of these layers are calculated, based on the performance of actual implementations of these protocols. The analysis presented seeks to quantify time delays within the context of protocols suitable for use with a high-speed local area network such as the fiber distributed data interface. The results presented verify that the transport and LLC software structures dominate the end-to-end message delays. A network interface implementation is presented which provides a merging of the layered protocols in such a way as to improve the time-critical performance of the network interface, while maintaining a logical mapping of the protocol functions to this new structure.<>