Stability of asynchronous ALOHA system (Q800287)

Problems of nonslotted ALOHA channel stability are considered in the paper. A theoretical model of such channel is described first and a criterion of channel stability is defined. It is proved that a user and the channel are stable in the sense of the above criterion if the average intensity of packet arrival at each system user is smaller than the reverse of the average packet service time needed by this user. The optimum probability distribution of packet arrival which maximizes channel utilization is found and it is shown that the maximum utilization of the nonslotted channel may reach the maximum utilization of the slotted channel for this probability distribution and infinite user population. Conditions for nonslotted channel instability are finally obtained. It is a pity that the authors do not make any remarks upon ALOHA channel stability analyses made previously and do not even mention papers treating of such analyses in the references.