Performance Evaluation Of Peer-To-Peer Structured Overlays Over Mobile Ad Hoc Networks Having Low Dynamism

To exploit the synergy between Mobile Ad hoc Networks (MANETs) and structured Peer-to-Peer (P2P) overlays, three different approaches, namely cross-layered, integrated, and layered have been proposed for their integration. In the cross-layered approach, information from the lower layers is made available at the application layer or vice versa. The integrated approach implements peer-to-peer routing algorithms at the network layer or MAC layer, whereas the layered approach utilizes application layer virtual links to construct P2P overlay on top of the MANET routing layer. It has been observed that cross-layered approach and integrated approach perform relatively better in situations where both node mobility and churn rate are high, but these approaches require changes in the lower layers of the protocol stack. On the other hand, the layered approach does not require any change in the protocol stack at lower levels, thus facilitating easy implementation. However, under highly dynamic scenarios this approach fails to achieve satisfactory performance. This paper targets to analyze the performance of layered approach under low dynamism. We have evaluated the performance of two topologically different structured overlays utilizing the layered approach in scenarios where, mobility of nodes is minimal, churn rate is low and network size is limited. The performance evaluation has been done using different network sizes, mobility speeds and lifetimes of nodes. Further, the frequency of execution of overlay maintenance procedures is also varied according to the dynamics of the MANET. The simulation results are gathered and compared with respect to packet delivery ratio, latency and maintenance overhead. The results obtained establish the applicability of layered approach for implementation of structured overlays over MANETs having low dynamism.