Abstract: Invention of wireless network has brought up drastic change in networking. Mobile Ad hoc NETwork (MANET) has been evolved as one of the promising technology based on implementation of wireless network. Providing mobility, flexible infrastructure, fast and low cost deplyoment are the key features of MANET. MANET is being most widely used wireless technology has limited security against network attacks. Dynamic configurability adds flexibility to MANET but it makes it vulnerable to attacks like DoS, Wormhole, Man-In-Middle Attack, IP Spoofing Attacks.