A multiaccess model for packet switching with a satellite having some processing capability

A multiaccess model for packet switching with a satellite having the capability of interrogating the uplink header and creating the downlink header is proposed. The satellite broadcasts slot assignments, based on the users' reported queue status, to the users for transmission in the next frame. With the protocols being done at both the earth stations and at the satellite, the proposed multiaccess model avoids collisions that are prevalent in schemes of the ALOHA type. The actual model is too complex to handle analytically. We derive analytical equations for a two-group model. Calculated and simulated buffer overflow probabilities as a function of traffic intensity and buffer size are compared. We also evaluate the performance of the actual model in terms of average system delay as a function of traffic intensity by means of computer simulation.