Um protocolo de tolerância a ataques de tunelamento em redes sensores sem fio

Abstract

This work proposes a security protocol against wormhole attacks in wireless sensor networks (WSN), based in message monitoring by base station and use of alternative paths. WSN are ad hoc networks,comprised of centuries of small sensor devices, used to monitor areas of interest. Its application goes since use in battle fields until environmental protection. The devices, also called sensor nodes, have limited resources for processing and communicating. Data collected by nodes are sent towards the base station, through routes created to this finality. WSN can suffer several types of attacks performed by maliciousnodes or invaders. The wormhole attack generally is accomplished by two colluded nodes. Their strategy is to attract to themselves the most of routs and messages. After that they can act on messages they receivein several ways. The most common action is to drop them, creating a shadow zone in the network, from where no data can be obtained. Solutions based on cryptography or massage authentication are noteffective to avoid it, because the opponent doesnt need to break messages contents to setup the attack. Also this kind of enemy can be superior equipment in terms of computational resources e radio capability compared to the common nodes making its combat a hard task. The solution we propose allows a WSN accomplish its work even during a wormhole attack, with a minimum message loss creating a tolerant attack security protocol. On experiments performed the results were around 90% of gain or higher to 500 nodes networks and attack rate of 70% and over.