Biblio

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.

MANET (Mobile ad-hoc network) is a wireless network. Several mobile nodes are present in MANET. It has various applications ranging from military to remote area communication. Several routing protocols are designed for routing of the packets in the network. AODV (ad hoc on demand vector) is one such protocol. Since, nodes are mobile in the network, security is a main concern. Blackhole attack is a network layer attack that tries to hamper the routing process. In this attack the data packets are dropped. The paper focuses on the analysis of AODV routing protocol under blackhole attack. First we have implemented blackhole attack in AODV and then analyzed the impact of blackhole attack on AODV under metrics like throughput, end to end delay and packet delivery fraction.

MANET is an infrastructure less, dynamic, decentralised network. Any node can join the network and leave the network at any point of time. Due to its simplicity and flexibility, it is widely used in military communication, emergency communication, academic purpose and mobile conferencing. In MANET there no infrastructure hence each node acts as a host and router. They are connected to each other by Peer-to-peer network. Decentralised means there is nothing like client and server. Each and every node is acted like a client and a server. Due to the dynamic nature of mobile Ad-HOC network it is more vulnerable to attack. Since any node can join or leave the network without any permission the security issues are more challenging than other type of network. One of the major security problems in ad hoc networks called the black hole problem. It occurs when a malicious node referred as black hole joins the network. The black hole conducts its malicious behavior during the process of route discovery. For any received RREQ, the black hole claims having route and propagates a faked RREP. The source node responds to these faked RREPs and sends its data through the received routes once the data is received by the black hole; it is dropped instead of being sent to the desired destination. This paper discusses some of the techniques put forwarded by researchers to detect and prevent Black hole attack in MANET using AODV protocol and based on their flaws a new methodology also have been proposed.