A cross-layer approach for neighbor discovery in opportunistic networks

In opportunistic networks, the Epidemic Routing (ER) protocol can offer a reliable way to transmit data. However, it has some extra latency in neighbor discovery. To address the problem, we propose a cross-layer approach to sense encountered nodes more quickly, which utilizes HELLO packets instead of the IMEP protocol to sense neighboring nodes, speeds sensing encountered nodes through cross-layer overhearing in MAC layers, and varies the period of HELLO packets to diminish unnecessary delivery of control packets. Results obtained from a series of simulation experiments show that our proposed approach outperforms the classical Epidemic Routing protocol and one of its present improvements in terms of the time of neighbor discovery and end-to-end packet delay.