Biblio

WSN can be termed as a collection of dimensionally diffused nodes which are capable of surveilling and analyzing their surroundings. The sensors are delicate, transportable and small in size while being economical at the same time. However, the diffused nature of these networks also exposes them to a variety of security hazards. Hence, ensuring a reliable file exchange in these networks is not an easy job due to various security requirements that must be fulfilled. In this paper we concentrate mainly on network layer threats and their security countermeasures to overcome the scope of intruders to access the information without having any authentication on the network layer. Various network layer intrusions that are discussed here include Sinkhole Attack, Sybil Attack, Wormhole Attack, Selective Forwarding Attack, Blackhole Attack And Hello Flood Attack.