Mobile ad hoc network simulation : analysis and enhancements
Yan Li · OpenGrey (Institut de l'Information Scientifique et Technique) · 2008
A Mobile Ad-Hoc Network (MANET) is a network consisting of mobile nodes communicating wirelessly. No infrastructure is required, so the nodes have to organise themselves into a network and establish routes in a distributed using distributed self organising algorithms. Routing protocols designed for wired networks are usually unsuitable for MANETs. Simulation has been the main tool for evaluating routing protocols, but differences in assumptions have made it difficult to compare results from different research groups. A characterisation ofMANETs based on quantifying the dynamic aspects of network topology is proposed and shown to be important for analysing performance. The popular random waypoint model (RWP) for node mobility is investigated. When the dynamic measures we propose are simulated, it is found that a very long warm-up period is required. Many published results are based on much shorter simulation experiments, causing us to doubt their validity. To overcome the long initial transient, we analyse the steady state distribution of node location when the RWP is used. A new network topology generation mechanism, the network reorganization model (NR), allows the creation of networks with the same dynamic characteristics as the RWP in a more controllable manner. A classification framework for routing protocols is proposed, based on the functions that a protocol must or may perform. Using this Functional Element Based Framework (FE~F), a large number of proposed and existing protocols from the literature are classified, giving clear insight into the relationships between different protocols.