Secure routing to avoid black hole affected routes in MANET

Mobile ad-hoc networks (MANETs) are becoming popular with proliferation of mobile devices. MANETs have infrastructure less property which makes them easily deployable and very dynamic in nature. The characteristics of MANET like open medium, lack of centralized monitoring and management may be maliciously used by the attacker to induce attacks. Black hole attack is prevalent in all wireless networks. It sends forged route reply (RREP) without knowing actual route to destination. Presence of such node in a network may disrupt the normal routing process of commonly used protocols such as AODV, DSR and so on. Protocols in MANET are not designed to detect black hole nodes or black hole affected routes. Therefore this paper proposes a DSR-based secure routing to detect black hole attack. The proposed solution, attaches a validity value with RREP. This validity value is checked by the first intermediate hop along the route reply and ensures that there is no black hole attack along the path.