Multiple access algorithms for a system with mixed traffic: High and low priority

A system is considered where a single channel is shared by both high and low priority data. We assume packet transmissions from both data categories and slotted channel. In addition, we assume binary, collision versus noncollision, feedback per slot, and limited feedback sensing capabilities for all users in the system. We assume that the high priority data are generated by a well-defined finite-number user population, while we adopt the limit Poisson User model (infinitely many independent Bernoulli users) for the low priority traffic. For this system, we propose and analyze a transmission algorithm, which is a mixture between a deterministic tree search, for the high priority users, and a random-access algorithm, for the low priority traffic. The algorithm is stable for both traffic classes, it guarantees a strict upper bound on the delays of the high priority packets, and induces good throughput-delay characteristics for the low priority data.