Graph-based wormhole attack detection in mobile ad hoc networks (MANETs)

A Mobile ad hoc network (MANET) is a set of nodes that communicate together in a cooperative way using the wireless medium, and without any central administration. Due to its inherent open nature and the lack of infrastructure, security is a complicated issue compared to other networks. That is, these networks are vulnerable to a a wide range of attacks at different network layers. At the network level, malicious nodes can perform several attacks ranging from passive eavesdropping to active interfering. Wormhole is an example of severe attack that has attracted much attention recently. It involves the redirection of traffic between two end-nodes through a Wormhole tunnel, and manipulates the routing algorithm to give illusion that nodes located far from each other are neighbors. To handle with this issue, we propose a novel detection model to allow a node to check whether a presumed shortest path contains a Wormhole tunnel or not. Our approach is based on the fact that the Wormhole tunnel reduces significantly the length of the paths passing through it.

I. Introduction

With the fast development of wireless technology, mobile ad hoc networks have become increasingly used in many areas and in different forms. An ad hoc network is a set of communicating entities or nodes having one or more wireless interfaces. This type of network is deployed without preexisting infrastructure and established dynamically without centralized administration. The lack of a central authority and a predefined infrastructure require that all nodes are actively involved in network functions such as routing, addressing, security, etc. One of the main advantages of ad hoc networks lies in reducing costs of implementation, since such networks require no prior infrastructure for their operation [1]. Ad hoc networks are used in several domains [2]–[4], such as military applications, rescue operations, commercial and industrial applications, etc. Despite their many benefits, ad hoc networks are subjected to several challenges. In addition to its wireless nature, MANET is vulnerable to attacks [5] [6] for many other reasons such as lack of infrastructure, limited physical protection and resources constraints. Among the most severe attacks against these networks, we are interested by those disrupting the routing process, precisely the Wormhole attack. To do this attack, a malicious node captures traffic in one location in the network, and forwards it to another malicious node at a remote location. This can be done using a tunnel created by two malicious nodes. The tunnel may be established in different ways: out-of-band channel, encapsulation, transmission at a high power, etc. Therefore, packets passing through the tunnel arrive first or with a smaller number of hops compared with other packets transmitted through a legitimate route.