Performance Analysis of Relayed-Broadcasting with Probabilistic Flooding in WLANs

Abstract

In this paper, we consider a relayed-broadcasting mechanism in IEEE 802.11 wireless local area networks (WLANs), to broadcast data traffic beyond the coverage of a source node. For this purpose, we adopt a probabilistic flooding scheme with which each intermediate node rebroadcasts received frames in a probabilistic manner to restrict unnecessary broadcasting of duplicate frames, as well as to decrease frequent collisions or interference due to simultaneous transmissions. In the relayed-broadcasting, there occurs a fundamental and inevitable tradeoff between reliable broadcasting and fast dissemination. To deal with this tradeoff, we consider two schemes of probabilistic flooding, named as relay-oriented flooding and reception-oriented flooding. The former is devised to improve the reliability of broadcasting, while the latter is devised to decrease the dissemination time. Via a simple analysis and extensive simulations, we compare the performance of these two schemes of probabilistic flooding in various aspects. The simulation results reveal interesting results and drawbacks of probabilistic flooding, which can be a basis for developing an effective relayed-broadcasting mechanism as our future work.