International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2013): 6.14 | Impact Factor (2014): 5.611 Volume 5 Issue 2, February 2016 www.ijsr.net Licensed Under Creative Commons Attribution CC BY A Review Paper on Preventing Forged Acknowledgement in Manets Ajit N. Gedam 1 , M. P. Wankhade 2 1 ME (Computer Network), Department of Computer Engineering, Sinhgad Collage of Engineering, Vadgaon (Bk), Pune. 411041, India 2 Associate Professor, Department of Computer Engineering, Sinhgad Collage of Engineering, Vadgaon (Bk), Pune. 411041, India Abstract: MANET is a group of mobile nodes that establish themselves into a network without any predefined infrastructure or centralized operation management. Mobile ad hoc networks are advantageous in situation such as flood or earthquake. MANET can quickly be established even though the network infrastructure is unavailable. It is very hard to detect and prevent forged acknowledgement. To prevent from forged acknowledgement, detection of misbehavior nodes plays an important role in MANETs. Dynamically changing topology, limited battery power and absence of centralized control in MANETs, make them vulnerable to detection of misbehavior nodes. Intrusion Detection System (IDS) is required to detect the misbehavior nodes before they can accomplish any significant damages to the network. Keywords: MANET; EAACK; DSA; RSA; Digital Signature; ACK; S-ACK; MRA 1. Introduction By definition, a mobile ad hoc network is a constantly self- configuring, self-maintained infrastructure less network of mobile devices which are associated without wires. Mobile ad hoc network consists of mobile nodes. These mobile nodes, which can communicate with each other in bidirectional way having wireless transmitting and receiving factor in network, directly or indirectly. Figure 1.1: MANETs Architecture Nodes are communicate with each other by using wireless network and various components and maintained its mobility. If nodes or components are not in the same range then use mobile ad hoc network. But to obtained this MANET which is divided into two different networks one is called as single hop network, in single hop network nodes which are present in the same range they can interact with each other directly, i.e. no any common nodes used in between. Another is multi-hop network, in which nodes rely on other intermediate nodes to transmit if the destination node is out of their radio range. Furthermore, because of MANET’s distributed architecture and changing topology, a traditional centralized monitoring technique is no longer possible in MANETs. In such case, it is crucial to develop an intrusion-detection system (IDS). It is observed that most of existing routing protocols have ignored the aspect of network security, specially designed for MANETs. The main purpose is to propose a new advanced system, which specially designed for MANET’s, which solves security issues during the packet transmission process. As in all acknowledgement base intrusion detection system, it is highly authenticated of all the acknowledgement packets. 2. IDS in MANETs Due to the limitations of most MANET routing protocols, nodes in MANETs assume that other nodes always cooperate with each other to relay data. This assumption leaves the attackers with the opportunities to achieve significant impact on the network with just one or two compromised nodes. To address this problem, an IDS should be added to enhance the security level of MANETs. If MANET can detect the attackers as soon as they enter the network, it will be able to completely eliminate the potential damages caused by compromised nodes at the first time. . In this section, mainly describe three existing approaches, namely, Watchdog, TWOACK, and Adaptive ACKnowledgment (AACK). 3. Forged Acknoledgement in MANETS In fact, many OF the existing IDSs in MANETs adopt an acknowledgment-based scheme, including TWOACK and AACK. The functions of such detection schemes all largely depend on the acknowledgment packets. Hence, it is crucial to guarantee that the acknowledgment packets are valid and authentic. To address this concern digital signature is adopted in scheme named Enhanced AACK (EAACK) to prevent forged acknowledgement. S-ACK modes of EAACK are digitally signed using Digital Signature Algorithm (DSA) to prevent the intermediate node from forging the S-ACK packet. 4. Literature Survey In [2] this paper the author suggested scheme contains two major parts, termed watchdog and path rater, to detect and mitigate, respectively. Nodes operate in a promiscuous mode wherein the watchdog module overhears the medium to check whether the next-hop node faithfully forwards the Paper ID: NOV161136 221