Securing Mobile Ad Hoc Networks (2004)

The vision of nomadic computing with its ubiquitous access has stimulated much interest in the Mobile Ad Hoc Networking (MANET) technology.Those infrastructureless, self-organized networks that either operate autonomously or as an extension to the wired networking infrastructure, are expected to support new MANET-based applications.However, the proliferation of this networking paradigm is strongly dependent on the availability of security provisions, among other factors.The absence of infrastructure, the nature of the envisioned applications, and the resource-constrained environment pose some new challenges in securing the protocols in the ad hoc networking environments.In particular, the security requirements can differ significantly from those for infrastructure-based networks, while the provision of security enhancements may take completely different directions as well.In this paper, we study the schemes proposed to secure mobile ad hoc networks.We expose the primary goals of security enhancements, shedding light on the commensurate challenges, and survey the up-to-date literature on this topic.Then, we introduce our approach to such a multifaceted and intriguing problem.Finally, we identify some open problems and plausible approaches.plausible for different network instances.Although the discussion throughout a great part of the paper lends itself to all types of ad hoc networks, it is important to realize that not all solutions can be applied in all ad hoc networking environments.Moreover, it is necessary to emphasize the relative importance of addressing certain security issues, which can be considered, to some extent, as prerequisites for solutions to other security problems.In the following sections, we will present the challenges posed by the MANET environment, survey the relevant literature, identify the limitations of the proposed approaches, and suggest directions for future solutions. Security GoalsThe overall problem of securing a distributed system comprises the security of the networked environment, and the security of each individual network node.The latter issue is important due to the pervasive nature of MANET, which does not allow us to assume that networked devices will always be under the continuous control of their owner.As a result, the physical security of the node becomes an important issue, leading to the requirement of tamperresistant nodes [24], if comprehensive security is to be provided.However, security problems manifest themselves in a more emphatic manner in a networked environment, and especially in mobile ad hoc networks.This is why in this work we focus on the network-related security issues.Security encompasses a number of attributes that have to be addressed: availability, integrity, authentication, confidentiality, non-repudiation and authorization.These goals, which are not MANET-specific only, call for approaches that have to be adapted to the particular features of MANET.First, we provide a generic definition of each goal, and, then, we expose in detail the challenges posed by this new networking paradigm.Availability ensures the survivability of network services despite misbehavior of network nodes; for instance, when nodes exhibit selfish behavior or when denial-of-service (DoS) attacks are mounted.DoS attacks can be launched at any layer of an ad hoc network.For example, an adversary could use jamming to interfere with communication at the physical layer, or, at the network layer, it could disrupt the routing protocol operation, disabling the operation of the route discovery procedure.Moreover, the adversary could bring down high-level services.One such target is the key management service, an essential service for an implementation of any security framework.Integrity guarantees that a message being transferred is not altered.A message could be altered because of benign failures, such as radio propagation impairments, or because of malicious attacks on the network.In addition, integrity viewed in the specific context of a connection, that is, the communication of two or more nodes, can provide the assurance that no messages are removed, replayed, reordered (if re-ordering would cause loss of information), or unlawfully inserted.Authentication enables a node to ensure the identity of the peer node that it is communicating with.Without