Fair media access for wireless LANs

摘要

This paper addresses load balancing algorithms for the wireless links to solve the fairness problem, where stations are not able to gain access equally to the shared wireless medium. The fairness problem occurs mostly because of the existence of hidden stations and the presumption of a non-fully connected wireless network topology. In this paper, p/sub ij/-persistent carrier sense multiple access based algorithms are proposed in which a fair wireless access for each user is accomplished using a pre-calculated link access probability. Link access probabilities are calculated at the source station in two ways using connection-based and time-based media access methods. Each active user broadcasts information on either the number of logical connections or the average contention time to the stations within the communication reach. Each station reserves a specific priority for its each link to gain access to the shared medium based on the exchanged information. The proposed algorithms are dynamic and sensitive to the changes in the network topology. They are applicable to all CSMA based media access control protocols to provide a degree of fairness.