Biblio

A self-governing system consisting of mobile nodes that exchange information within a cellular area and is known as a mobile ad hoc network (MANET). Due to its dynamic nature, it is vulnerable to attacks and there is no fixed infrastructure. To transfer a data packet Ad-hoc On-Demand Distance Vector (AODV) is used and it's another form of a reactive protocol. The black-hole attack is a major attack that drastically decreases the packet delivery ratio during a data transaction in a routing environment. In this attack, the attacker's node acts as the shortest path to the target node itself. If the attacker node receives the data packet from the source node, all obtained data packets are excluded from a routing network. A trust-based routing scheme is suggested to ensure secure routing. This routing scheme is divided into two stages, i.e., the Data retrieval (DR), to identify and preserve each node data transfer mechanism in a routing environment and route development stage, to predict a safe path to transmit a data packet to the target node.

A wireless sensor network consists of many important elements like Sensors, Bass station and User. A Sensor can measure many non electrical quantities like pressure, temperature, sound, etc and transmit this information to the base station by using internal transreceiver. A security of this transmitted data is very important as the data may contain important information. As wireless sensor network have many application in the military and civil domains so security of wireless sensor network become a critical concern. A Sybil attack is one of critical attack which can affect the routing protocols, fair resourse allocation, data aggregation and misbehavior detection parameters of network. A number of detection techniques to detect Sybil nodes have already designed to overcome the Sybil attack. Out of all the techniques few techniques which can improve the true detection rate and reduce false detection rate are discussed in this paper.