A probabilistic refined policy for topology-independent medium access control in ad hoc network environments

Abstract

Modern network environments are starting to engulf billions of different interconnected devices that support a wide range of applications. Depending on the case, these environments range from static (e.g., wireless sensors) to highly dynamic (e.g., vehicular networks) with respect to topology changes and have different constraints for throughput, time delay, energy consumption etc. Supporting such applications in a topology-varying ad hoc environment is a challenging task. Thus, TDMA-based MAC policies are revisited here and a new policy, i.e., the refined policy is proposed, which builds and improves on the topology-independent policies that appear in the literature. In particular, an individual access probability is introduced that is distributively calculated by each node to access time slots that may result to collisions, but if not then unused network resources will be utilized, thus, increasing throughput. The key idea under the refined policy is to identify and refrain from transmitting during slots that collisions are likely to appear. An analytical expression for the individual access probability is also derived here. It is also shown through simulation experiments that energy consumption is also reduced in addition to throughput incremented under the proposed policy.