Research on energy-efficient contact probing in Delay Tolerant Networks

In the Delay Tolerant Networks (DTNs), in order to discover the neighbors, the nodes in the network have to probe the surrounding environment continually. This can be an extremely energy-consuming process. If the nodes probe very frequently, they consume a lot of energy, and may be energy inefficient. On the other hand, infrequent contact probing might cause loss of many contacts, and thus missing the opportunities to exchange data. Therefore, there exists a trade-off between the energy efficiency and contact opportunities in the DTNs. In order to investigate this trade-off, this study first proposes a model to quantify the contact detecting probability when the contact probing interval is constant based on the Random Way-Point (RWP) model. Moreover, this study also demonstrates that the strategy which probes at a constant interval performs the best performance, among all contact probing strategies with the same average contact probing interval. Then, based on the proposed model, this study analyzes the trade-off between the energy efficiency and contact detecting probability under different situations. Finally, extensive simulations are conducted to validate the correctness of the proposed model.