Competition and cooperation in wireless access misbehavior

With the proliferation of access points and terminals, wireless access misbehavior emerges as important means of protocol misuse, whereby network entities aim at obtaining higher channel share than the one in legitimate operation. We consider the instantiation of misbehavior in the back-off mechanism in IEEE 802.11. First, we study the competition between two malicious entities that affect each other. Each entity has some private target gain in terms of access probability and attempts to misuse the protocol to its benefit so as to prolong the time until detection. We derive conditions for existence of the unique Nash Equilibrium Point (NEP). This is influenced by attacker gains and topology parameters that capture the level of contention from neighboring nodes. These quantities need to be small in order for the NEP to exist. Next, we consider simple types of cooperation between attackers that aim at alleviating the contention caused to each other. © 2011 IEEE