An ad-hoc network is a collection of wireless mobile nodes that forms a temporary network without any centralized administration. While early research effort assumed a friendly and cooperative environment and focused on problems such as wireless channel access and multihop routing, security has become a primary concern in order to provide protected communication between nodes in a potentially hostile environment. Recent wireless research indicates that the wireless MANET (Mobile Ad hoc Network) presents a larger security problem than conventional wired and wireless networks. In this paper we discuss various features of MANET due to which network is more susceptible to threats. We also analyze various attacks in MANET.

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Manet Black Hole Gray Hole Sybil Selfish Dos