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Mobile ad hoc networks face many challenges when they are deployed, particularly problems associated with security and network failures arising from the dynamics of their network topologies. To address these issues, there have been many efforts to introduce security into the actual network protocols, most of which unfortunately struggle with the trade-off between security and network overhead. Consequently, it is often desirable to have a lightweight approach to introduce security and robustness, where one employs conventional and well-understood network protocols, and attempts to achieve the assurability of the network through higher-layer, overlay mechanisms. This paper explores a lightweight overlay tunneling scheme operating at the Internet protocol layer as a policy tool that can mitigate network failures and attacks directed at the network without involving the redesign of the underlying routing protocols. Moreover, two optimizations are proposed that lead to improved performance when additional information is available. Copyright © 2016 John Wiley & Sons, Ltd.

Localization of wireless devices in wireless networks is important because the location of wireless devices is a critical input for many higher‐level networking tasks. Both the placement and the selection of anchors can affect the accuracy of location estimation significantly, and consequently impact the widespread deployment of location‐based services (LBSs). This chapter investigates the problems of anchor placement and anchor selection. It discusses how the geometric layout of the anchors affects the localization performance. Different approaches that include heuristic search methods, acute triangular‐based deployment, adaptive beacon placement, and optimal placement solutions via the maximum lambda and minimum error (maxL‐minE) algorithm are discussed. The chapter studies how smartly selected anchors can achieve comparable or better localization results as compared with using all the available anchors. A variety of effective strategies are investigated, including a joint clustering technique, entropy‐based information gain, convex hull selection, and smart selection in the presence of high density of anchors.

The nodes in a wireless ad hoc network act as routers in a self-configuring network without infrastructure. An application running on the nodes in the ad hoc network may require that intermediate nodes act as routers, receiving and forwarding data packets to other nodes to overcome the limitations of noise, router congestion and limited transmission power. In existing routing protocols, the ‘self-configuring’ aspects of network construction have generally been limited to the construction of routes that minimize the number of intermediate nodes on a route while ignoring the effects that the resulting traffic has on the overall communication capacity of the network. This paper presents a context-aware routing metric that factors the effects of environmental noise and router congestion into a single time-based metric, and further presents a new cross-layer routing protocol, called Warp-5 (Wireless Adaptive Routing Protocol, Version 5), that uses the new metric to make better routing decisions in heterogeneous network systems. Simulation results for Warp-5 are presented and compared to the existing, well-known AODV (Ad hoc On-Demand Distance Vector) routing protocol and the reinforcement-learning based routing protocol, Q-routing. The results show Warp-5 to be superior to shortest path routing protocols and Q-routing for preventing router congestion and packet loss due to noise. Copyright © 2011 John Wiley & Sons, Ltd. This paper presents a cross-layer predictor for route selection in wireless ad hoc networks that combines the effects of noise and router congestion into a single time-based routing metric based on statistical estimation from recent experience. A new cross-layer, adaptive routing protocol, called Warp-5, uses this new routing metric to make better routing decisions in noisy or congested wireless ad hoc networks.

Multi-hop routing is essential to the operation of wireless ad hoc networks. Unfortunately, it is very easy for an adversary to forge or modify routing messages to inflict severe damage on the underlying routing protocol. In this paper, we present SEAR, a secure efficient ad hoc routing (SEAR) protocol for ad hoc networks that is mainly based on efficient symmetric cryptography, with asymmetric cryptography used only for the distribution of initial key commitments. SEAR uses one-way hash functions to protect the propagation of the routing messages. Intermediate nodes verify the routing messages by applying one-way functions, while malicious nodes cannot construct beneficial false routing messages when forwarding them. Route error (RERR) messages are protected through a variation of the TESLA broadcast authentication scheme. The SEAR protocol does not require any additional routing packet formats, and thus follows the same basic design as ad hoc on-demand distance vector (AODV). We show, through both theoretical examination and simulations, that SEAR provides better security with significantly less overhead than other existing secure AODV (SAODV) protocols. Copyright © 2008 John Wiley & Sons, Ltd.

Vehicular ad hoc networks (VANETs) represent a promising new communication technology that can facilitate many new forms of automotive applications. Many of the applications that will run on these networks will require a high degree of security and privacy. In this paper, we present a robust and efficient security framework for vehicular networks suited for both inter-vehicular and vehicle-to-infrastructure communication. Our system uses identity-based cryptography (IBC) to provide authentication, confidentiality, non-repudiation, and message integrity. It exploits the implicit authentication provided by IBC to significantly reduce the security/privacy-related communication overhead. Additionally, it provides scalable, user-customizable security and privacy using short-lived, authenticated, and unforgeable, pseudonyms. This feature can be used by VANET applications that require quantifiable trust and privacy to provide differentiated service based on various levels of trust and privacy thresholds. Copyright © 2008 John Wiley & Sons, Ltd.