Towards Immunizing MANET's Source Routing Protocols against Packet Droppers

This paper deals with security of routing protocols of Mobile Ad hoc Networks (MANETs), and proposes a solution to immunize such protocols against packet dropping misbehavior. Most of the current secure protocols are vulnerable to packet dropping misbehavior, which can be exploited by selfish nodes and malicious ones as well. For example, simply by dropping RREQ (Route Request) packets a selfish node can exclude itself from routes and thereby avoid receiving data packets to forward. On the other hand, a malicious node can drop RERR (Route Error) packets to keep the use of failed routes, possibly resulting in a denial of service. To mitigate this vulnerability we propose a hybrid solution that secures routing protocols against the dropping of both directed and broadcast control packets, in which a different approach is adapted for each kind of packets. Dealing with control packets represents the main contribution in this manuscript, as all the current proposals in the context of selfish nodes only consider data packets. Our solution can be integrated with any source routing protocol. In this work it was implemented with one of the most secure protocols, namely ENDAIR. The resulting new extended secure protocol was assessed and analyzed through an extensive simulation study.