Abstract
A mobile ad hoc network (MANET) is a dynamic wireless network that can be fashioned without any pre-existing infrastructure in which every node can act as a router. MANET has no clear line of defense, so, it is available to both legitimate network users and malicious attackers. In the presence of malicious nodes, one of the most important challenges in MANET is to sketch the sturdy security answer that can guard MANET from worm-hole attack. Different mechanisms have been proposed the usage of digital signature methods to countermeasure the routing attacks against MANET. However, these mechanisms are no longer suitable for MANET aid constraints, i.e., limited bandwidth and battery power, due to the fact they introduce heavy traffic load to exchange and verifying keys. In this paper, the cutting-edge protection issues in MANET are investigated. Particularly, we have examined wormhole attack as well as existing options to defend MANET protocols.