A Light-weight Location-aware Position Update Scheme for High Mobility Networks

In a mobile networking environment, constant node motion result in drastic changes in spatial distribution of nodes which in turn causes changes in network topology. Blind position information updates could comprise a significant fraction of the network traffic. Consequently, maintaining accurate position information in such situations could become prohibitively expensive. In addition, the reference of information decreases as the distance increase, i.e., interest in position information could be highly localized and distant nodes do not require precise position description. In this paper, we propose a grid-based update mechanism that establishes the relationship between the grid-size and the frequency of position update. Such an association has two salient features: Firstly, only relevant updates based on location are transmitted avoiding redundant position updates. Secondly, it provides a guidance for adjusting the frequency of position updates in connection with the required positional accuracy and mobility pattern. We present an analysis of the performance of the proposed approach under the random walk mobility model, and proposes a fully distributed grid-based Markov model to capture the impact of mobility pattern on the frequency of position updates. We show in the simulation experiment that the proposed grid-based position update mechanism can reduce the network overhead for position updates by more than 65% while affecting the positional accuracy by less than 3%.