Selfish Misbehavior Detection in CSMA Cooperative Networks withHARQ

In wireless cooperative transmissions, nodes may deviate from the cooperative protocol to reduce energy consumption while still reaping the benefits of other nodes' cooperation. Misbehavior is implemented by refraining from responding to cooperation request, mimicking adverse channel conditions. From time to time (with a given percentage) cooperations requests are accepted in order to avoid being detected as selfish. In this paper, we propose a technique for detecting misbehavior of nodes in an ad hoc network using carrier sense multiple access (CSMA) and automatic repeat request (ARQ) protocol. Each node can detect control packets of ARQ among source, destination and cooperating nodes, and collect statistics on their decoding probability. Selfish behavior is detected based on uniformly most powerful (UMP) test which yields the minimum miss detection probability for a given false alarm probability

Detection of selfish partners by control packets in ARQ-based CSMA cooperative networks

Cooperation in wireless networks is beneficial for both throughput and power consumption, but requires that nodes are willing to cooperate. As the Nash equilibrium for each node would be a non-cooperative strategy, monitoring nodes\u2019 behavior is essential to ensure cooperation. In this paper we present a monitoring approach for networks implementing automatic repeat request (ARQ) and carrier sense multiple access (CSMA). Node misbehavior is detected by listening to all control packets in the network and comparing the packet decoding probability when the monitored node is a destination and when it is a potential cooperator. For this detection strategy, we derive the false alarm and miss detection probabilities, which allow to properly design the system parameters. In order to further improve detection, we propose a distance-based method, where the estimate of the decoding probabilities is improved by enforcing geometric constraints on position of nodes. Both analytical and simulated results are presented for a wireless network characterized by both path-loss and fading

Detection of selfish nodes in networks using CoopMAC protocol with ARQ

CoopMAC has been recently proposed as a possible implementation of cooperation protocols in the medium access control (MAC) layer of a wireless network. However, some nodes may refrain from cooperation for selfish purposes, e. g. in order to save energy, in what is called selfish behavior or misbehavior. This protocol violation worsens other nodes' performance and can be avoided if other nodes detect and punish (e. g. banning from the network) misbehaving nodes. However, fading and interference may prevent nodes from cooperating even if they are willing, therefore it is not trivial to identify misbehaving nodes. In a fading scenario where an automatic repeat request (ARQ) protocol is used, we propose a mechanism that allows to detect misbehaving nodes. Two approaches, either based on the uniformly most powerful (UMP) test or on the sequential probability ratio test (SPRT) are considered. The two techniques are characterized and compared in terms of their average detection delay and resulting network performance

Sequential detection of misbehaving nodes in cooperative networks with HARQ

Existing cooperative communications protocols are designed with the assumption that users always behave in a socially efficient manner. This assumption may be valid in networks under the control of a single authority where nodes cooperate efficiently to achieve a common goal. On the other hand, in commercial wireless networks where nodes are individually motivated to cooperate, the assumption that nodes will always obey rules of cooperation may not hold without implementing a mechanism to detect and mitigate misbehavior. In this paper, we present a sequential misbehavior technique based on sequential probability ratio test (SPRT) for cooperative networks using automatic repeat request (ARQ). We evaluate performance of the detection technique both analytically and using numerical methods