Abstract: Mobile ad hoc Networks (MANETs) is an autonomous assortment of mobile nodes that type form network with none existing network infrastructure or central access point. Since MANETs need a novel, distinct, and protracted identity per node so as for his or her security protocols to be viable, Sybil attacks cause a heavy threat to such networks. Sybil attacker will lawlessly claim multiple identities on single node and violate one-to-one mapping. Masquerading is an active attack where one node pretends to be another and giving false impersonation. Here by using RSS (Received Signal Strength) of nodes to find Sybil and masquerading identities on network with good accuracy even in the presence of mobility. This scheme detect Sybil identities while not exploitation centralized trusty third party or any further hardware, like directional antennae or a geographical positioning system.

Keywords: Mobile Ad hoc Networks (MANET), Received Signal Strength, Sybil Attack, Masquerading Attack, Security.