Abstract: “Wireless networks are gaining popularity to its peak today, as the users want wireless connectivity irrespective of their geographic position. There is an increasing threat of attacks on the Mobile Ad-hoc Networks (MANET). Black hole attack is one of the security threat in which the traffic is redirected to such a node that actually does not exist in the network. MANETs must have a secure way for transmission and communication which is quite challenging and vital issue. In this paper, a brief overview is given about the black hole attack on MANETs and various kind of routing protocols which get affected by the Black Hole attack along with an overview about the countermeasures to avoid it.”

Keywords: MANETs, AODV, Routing protocol, black hole attack.