Defense against Lap-top Class Attacker in Wireless Sensor Network

security and focus our attention to tolerate damage caused by an adversary who has compromised deployed sensor node to modify, block, or inject packets. We adopt a probabilistic secret sharing protocol where secrets shared between two sensor nodes are not exposed to any other nodes. Adapting to WSN characteristics, we incorporate these secrets to establish new pairwise key for node to node authentication and design multi-path routing to multiple base stations to defend against HELLO flood attacks. We then analytically show that our defense mechanisms against HELLO flood attack can tolerate damage caused by an intruder. Keywords ⎯ Routing Security, Multi-path Routing