Group mobility impact over TCP and CBR traffic in mobile ad hoc networks

We present an analysis of the effect that mobility models have over the performance of a mobile ad hoc network. We concentrate on group mobility because there is a growing attention on the development and evaluation of MANET´s approach applied to personal area networks (PANs), especially based on Bluetooth technology. We investigate the effect that the mobility model has on the performance of CBR traffic and TCP traffic. We propose four different group mobility models and describe a mobility pattern generator called grcmob to be used with the ns-2 simulator. We perform a thorough evaluation of a MANET behavior using as a reference the behavior obtained with the random waypoint mobility model. We observe the high variability of the results and the need to know exactly the behavior of the system and the impossibility to define a unique proposal which is general to whatever environment. We make evident that group mobility pattern highly affects the performance of both CBR traffic and TCP traffic. Also the mix of inter- and intra-group communication has a strong impact on the MANET performance and should therefore be taken into consideration when tuning or designing MANETs protocols.