Catching Packet Droppers and Modifiers in Wireless Sensor Networks

Introduction:

                                  In a wireless sensor network, sensor nodes monitor the environment, detect events of interest, produce data and collaborate in forwarding the data towards a sink, which could be a gateway, base station, storage node, or querying user. Because of the ease of deployment, the low cost of sensor nodes and the capability of self-organization, a sensor network is often deployed in an unattended and hostile environment to perform the monitoring and data collection tasks. When it is deployed in such an environment, it lacks physical protection and is subject to node compromise. After compromising one or multiple sensor nodes, an adversary may launch various attacks to disrupt the in-network communication. Among these attacks, two common ones are dropping packets and modifying packets, i.e., compromised nodes drop or modify the packets that they are supposed to forward. To deal with packet droppers, a widely adopted countermeasure is multi-path forwarding, in which each packet is forwarded along multiple redundant paths and hence packet dropping in some but not all of these paths can be tolerated. To deal with packet modifiers, most of existing countermeasures aim to filter modified messages en-route within a certain number of hops. These countermeasures can tolerate or mitigate the packet dropping and modification attacks, but the intruders are still there and can continue attacking the network without being caught. In this paper, we propose a simple yet effective scheme to catch both packet droppers and modifiers.

Scope of the Project:

                              Our proposed scheme has the following features: (i) being effective in identifying both packet droppers and modifiers, (ii) low communication and energy overheads, and (iii) being compatible with existing false packet filtering schemes; that is, it can be deployed together with the false packet filtering schemes, and therefore it can not only identify intruders but also filter modified packets immediately after the modification is detected.