Performance analysis of an access method suitable for the integration of voice and data

This contribution describes a new type of an integrated system's architecture which reconciles the diverging needs of both, stream traffic of 64 kbit/s and bursty traffic of low and high data rates. The total capacity of a unidirectional bus is subdivided into a high-speed channel and a certain number of time slots for stream traffic. The capacity of the high-speed channel can dynamically be adjusted according to the amount of time slots required for stream traffic. Due to the dynamic creation and deletion of time slots, the subsystem for 64-kbit/s channels is almost blocking-free. The same mechanism is used to control access to the high-speed channel, and to determine the fraction of the total capacity dedicated to the high-speed channel. The performance of the proposed access mechanism has been investigated by means of system modelling and simulation. The results show that besides its ability to accommodate 64-kbit/s channels it compares quite favourably with other LAN concepts like CSMA/CD.