A Survey on Multihop Ad Hoc Networks for Disaster Response Scenarios

Disastrous events are one of the most challenging applications of multihop ad hoc networks due to possible damages of existing telecommunication infrastructure. The deployed cellular communication infrastructure might be partially or completely destroyed after a natural disaster. Multihop ad hoc communication is an interesting alternative to deal with the lack of communications in disaster scenarios. They have evolved since their origin, leading to different ad hoc paradigms such as MANETs, VANETs, DTNs, or WSNs. This paper presents a survey on multihop ad hoc network paradigms for disaster scenarios. It highlights their applicability to important tasks in disaster relief operations. More specifically, the paper reviews the main work found in the literature, which employed ad hoc networks in disaster scenarios. In addition, it discusses the open challenges and the future research directions for each different ad hoc paradigm.

Reducing Throughput-delay Analysis of Conflict–free Scheduling in Multihop Adhoc Networks

An Adhoc networks is a self organized and distributed entity, consisting of n mobile stations (MSs) without the coordination of any centralized access point. Initialization is one of the fundamental tasks to set up an adhoc network, which involves assigning of each of the n MSs a distinct ID number from 1 to n, distributedly. In randomized initialization protocols are developed for single-hop adhoc networks under different conditions. This study investigates the performance of an analytical approximation for the throughput-delay charac-teristic of a multihop ad-hoc network employing conflict-free time division multiplex (TDM) scheduling with half-duplex transceivers. The approximation models traffic at each link as an independent M/D/1 queue and its perfor-mance is measured by comparing to simulation results for various topologies, traffic loads, and network sizes. Re-sults indicate that the approximation is most appropriate for a tandem network but is also reasonable for other two-dimensional topologies. In the twodimensional topologies, the approximation clearly improves at high traffic loads but does not exhibit distinguishable trends over the network sizes observed.