1 A lightweight technique for detection and prevention of wormhole attack in MANET Zulfiqar Ali Zardari 1 , Kamran Ali Memon 2,* , Reehan Ali Shah 3 , Sanaullah Dehraj 4 , Iftikhar Ahmed 5 1 Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China 2 School of Electronic Engineering, Beijing University of Posts & Telecommunications, Beijing, China 3 Department of computer system Engineering, faculty of Engineering, The Islamia University Bahawalpur, Pakistan 4 Department of Mathematics and Statics, Quaid e Awam University of Engineering, Science and Technology, Nawabshah, Pakistan 5 School of Computer science, Beijing Institute of Technology, China Abstract A mobile ad-hoc network (MANET) is an ordinary and self-orbiting communication network that is capable of managing mobile nodes. Many proposed protocols on MANET address its vulnerability against different threats and attacks. The malicious node exploits these vulnerabilities to lunch attacks, especially when nodes have mobility and network do not have constant topology, like wormhole attack. This paper presents a lightweight technique that detects the wormhole attacks in MANET. In the proposed technique, the source node calculates the average sequence number of the reply (RREP) packets. If the sequence number of the corresponding node exceeds the calculated average value of the sequence number, then all traffic is discarded, and the node is marked as malicious. The proposed technique is less complex, power-efficient, and enhances network lifetime as more data packets are delivered to the destination node. This technique is validated through comprehensive simulations results in NS2 Keywords: MANET, Denial of service, Wormhole attack, Average sequence number, Reply (RREP) packet Received on 16 May 2020, accepted on 04 July 2020, published on 08 July 2020 Copyright © 2020 Zulfiqar Ali Zardari et al., licensed to EAI. This is an open access article distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/3.0/), which permits unlimited use, distribution, and reproduction in any medium so long as the original work is properly cited. doi: 10.4108/eai.13-7-2018.165515 1. Introduction Mobile Ad-hoc Network is a wireless network without any infrastructure which includes mobile nodes that can move according to a pattern, and the topological structure of the network keeps on changing dynamically. The routes between any two nodes are made through the intermediate hops on the ad-hoc basis, i.e., these routes are temporary and may disrupt with the passage of time due to several factors. Due to the dynamic nature of MANET is considered as a distributed network [1] in which a large number of nodes exchange information through symmetrical or asymmetrical radio links in a multi-hop manner. In MANET, nodes can act as intermediate hop or router to provide a route between two end nodes that can communicate through this path formed by intermediate nodes. These paths are formed using one of several standards or customized routing protocols following a specific mechanism linked to those protocols which can be categorized as proactive, reactive, and hybrid [2]. All these routing protocols might create a loophole in the security of the network due to their intrinsic properties. All these features of MANET pave the way for a wide range of both active as well as passive attacks [3] that makes the issue of data security of critical importance. Even with these drawbacks, MANET has the bulk of features that makes it successful in various fields. MANET finds its application in the field where it is difficult to set up a wired network with centralized or decentralized infrastructure with fixed base stations around which the entire network is controlled [4]. MANET proves to be handy on these occasions as it involves mobile nodes that build paths and communicate act in a spontaneous and ad-hoc manner. MANET network is used for disaster management, rescue operations, military communication services, short-range communications, etc. reason it is very cheap as compared EAI Endorsed Transactions on Scalable Information Systems Research Article *Corresponding author. Email: Ali.kamran77@gmail.com EAI Endorsed Transactions Scalable Information Systems 12 2020 - 01 2021 | Volume 8 | Issue 29 | e2