Mobile Ad-hoc Network (MANET) is a application of wireless network with self-configuring mobile nodes. MANET will not need any mounted infrastructure. Nodes in MANET will communicate with every alternative nodes if and provided that all the nodes square measure within the same vary. This distribution of nodes makes MANET vulnerable to varied attacks, packet dropping attack or black hole attack and replay are some of the possible attacks. It is very heavy to notice and preclude. To prevent from packet dropping attack, detection of misbehaviour links and egotistical nodes plays a necessary role in MANETs. In this paper we are going to compare all technique how they notice the self-absorbed link and malicious node.