Secure DSR Routing from Malicious Node by PGP Encryption

Mobile ad hoc network (MANET) is an infrastructure less, self organizing on demand wireless communication. The nodes communicate among themselves through their radio range and nodes within the range are known as neighbor nodes. DSR (Dynamic Source Routing), a MANET reactive routing protocol identify the destination by transmitting route request (RREQ) control message into the network and establishes a path after receiving route reply (RREP) control messages. The intermediate node lies in between source to destination may also send RREP control message, weather they have path information about that destination is present into their route cache due to any previous communication. A malicious node may enter within the network and may send RREP control message to the source before original RREP is being received. After receiving RREP without knowing about the destination source starts to send data and data may reached to a different location. In this paper we proposed a novel algorithm by which a malicious node, even stay in the network and send RREP control message but before data transmission source can authenticate the destination by applying PGP (pretty Good Privacy) encryption program. In order to design our algorithm we proposed to add an extra field with RREQ control message with a unique index value (UIV) and two extra fields in RREP applied over UIV to form a random key (Rk) in such a way that, our proposal can maintained two way authorization scheme. Even a malicious node may exists into the network but before data transmission source can identified weather RREP is received by the requested destination or a by a malicious node.