RRAND: A New Requirement Aware RAND based Flexible Slot Allocation Mechanism Optimized For Spatial Reuse Of Slots

Schedule based MAC schemes do not perform well for dynamic network and traffic conditions. Their inflexibility makes them unsuitable for most real life applications. This inflexibility is due to the nature of schedule based approach. However, it depends mainly on the re-scheduling and slot allocation strategies employed. A flexible schedule based scheme should allow for the nodes to access the medium with different periodicity. The periodicity should be based on their traffic requirements which may result in improved channel utilization. However, traditionally used slot allocation protocols, e.g. RAND[1], do not consider the required medium access periodicity while allocating slot to the node. Thus, resulting schemes are not flexible to dynamic traffic conditions. This results in bandwidth wastage. In this paper, we propose a new flexible requirement aware RAND (RRAND) mechanism to allocate slots efficiently. Through simulations we show that our mechanism improves channel utilization on an average by about 60 %. The fairness characteristics are also improved significantly.