Robust Packet Delivery

Robust and reliable packet delivery in mobile ad hoc networks requires dealing with unstable links. Focus of this report is on two methods to mitigate this problem. Firstly, we study Cross-Packet Coding which uses forward error correction to protect an IP packet end-to-end through a network. We show that it can provide a substantial increased packet delivery ratio when a packet is so large that it cannot be sent in one transmission but need to be fragmented into several transmissions. Secondly, we investigate the network diversity which provides robustness through redundancy if a message is transmitted over several paths between a source and a destination. By simulations we estimate the amount of network diversity that is utilized by MPR flooding. The network diversity in the studied networks is equivalent to between one and two independent paths depending on network density.