User Differentiation Scheme for Slot Allocation in Vehicular Networks

In this paper, we propose a two-phase based user differentiation scheme (UDS) for slot allocation in vehicular networks. Vehicular nodes in our proposed scheme are divided into two types: the backbone nodes and the ordinary nodes. In the first phase, every vehicular node tries to occupy one time slot with the same behavior, and at the end of the first phase based on the received broadcast packets during one frame vehicular nodes who have more neighbors can be upgraded to backbone nodes. During the second phase the backbone nodes carry out a greedy behavior to contend for more time slots while ordinary nodes give up slot contention. The slot occupation period and the dynamically backbone node selection strategy are given in detail. Moreover, the performance of average channel utilization and broadcast delay have been analyzed. Analysis and simulation results show that the proposed UDS has a better performance in the two indexes listed above compared to the one-to- one scheme without user differentiation.