Data replication effectiveness in mobile ad-hoc networks

Abstract

In this paper the behavior of a MANET when, for several reasons, the node density varies in such a way to cause subnet disconnections, is considered. Data replication is usually employed to avoid data loss in case of unwanted disconnection of a node, increasing its availability. Considering a time-scale connectivity and node mobility, replicas can be distributed over the net, in order to make data available even during disconnection periods.A formula can be derived, which allows to evaluate the replica availability in different scenarios, using the probability density functions describing the partitioning of a network obtained by a simulator. Applying this formula to different kind of networks, it is possible to tune the degree of replication desired for different scenarios, looking for a trade-off between space occupancy and availability gain.