Ad hoc wireless distribution service

About: Ad hoc wireless distribution service is a research topic. Over the lifetime, 17734 publications have been published within this topic receiving 488205 citations.

A Probabilistic Emergent Routing Algorithm for Mobile Ad Hoc Networks

Abstract: Mobile ad hoc networks are infrastructure-less networks consisting of wireless, possibly mobile nodes which are organized in peer-to-peer and autonomous fashion. The highly dynamic topology, limited bandwidth availability and energy constraints make the routing problem a challenging one. In this paper we take a novel approach to the routing problem in MANETs by using swarm inteligenceinspired algorithms. The proposed algorithm uses Ant-like agents to discover and maintain paths in a MANET with dynamic topology. We present simulation results that measure the performance of our algorithm with respect to the characteristics of a MANET, the varying parameters of the algorithm itself as well as performance comparison with other well-known routing protocols.

Graph-based mobility model for mobile ad hoc network simulation

Abstract: Imagine a world where people constantly try to pass through walls and cars suddenly leave the roads and drive into rivers. Although this is unrealistic, most simulations for mobile ad hoc networks so far are based on the so called "random walk" of mobile objects, which are not constrained by their surrounding spatial environments. In this paper we propose a novel graph-based mobility model, which provides a more realistic movement than the random walk model by reflecting the spatial constraints in the real world. We analyzed three commonly used ad hoc network routing protocols, DSDV, DSR and AODV with both a random walk-based and our graph-based mobility model. Our simulation results show that the spatial constraints have a strong impact on the performance of ad hoc routing protocols.

Minimizing broadcast latency and redundancy in ad hoc networks

Abstract: Network wide broadcasting is a fundamental operation in ad hoc networks. In broadcasting, a source node end a message to all the other nodes in the network. In this paper, we consider the problem of collision-free broadcasting in ad hoc wireless networks. Our objective is to minimize the latency and the number of retransmission in the broadcast. We show that minimum latency broadcasting i NP-hard for ad hoc wireless networks. We also present a simple and distributed collision-free broadcasting algorithm for broadcasting a message. For networks with bounded node transmission ranges, our algorithm simultaneously guarantees that the latency and the number of retransmission are within O(1)times their respective optimal values. Our algorithm and analysis extends to the case when multiple messages are broadcast from multiple sources. Experimental studies indicate that our algorithm perform much better in practice than the analytical guarantee provided for the worst case.

Resource optimization of spatial TDMA in ad hoc radio networks: a column generation approach

Abstract: Wireless communications using ad hoc networks are receiving an increasing interest. The most attractive feature of ad hoc networks is the flexibility. The network is set up by a number of units in an ad hoc manner, without the need of any fixed infrastructure. Communication links are established between two units if the signal strength is sufficiently high. As not all pairs of nodes can establish direct links, the traffic between two units may have to be relayed through other units. This is known as the multihop functionality. Design of ad hoc networks is a challenging task. In this paper we study the problem of resource allocation with spatial TDMA (STDMA) as the access control scheme. Previous work for this problem has mainly focused on heuristics, whose performance is difficult to analyze when optimal solutions are not known. We develop, for both node-oriented and link-oriented allocation strategies, mathematical programming formulations for resource optimization. We further present a column generation approach, which, in our numerical experiments, constantly yields optimal or near-optimal solutions. Our results provide important benchmarks when evaluating heuristic on-line algorithms for resource optimization using STDMA.

Survey of clustering algorithms for MANET

Abstract: Many clustering schemes have been proposed for ad hoc networks. A systematic classification of these clustering schemes enables one to better understand and make improvements. In mobile ad hoc networks, the movement of the network nodes may quickly change the topology resulting in the increase of the overhead message in topology maintenance. Protocols try to keep the number of nodes in a cluster around a pre-defined threshold to facilitate the optimal operation of the medium access control protocol. The clusterhead election is invoked on-demand, and is aimed to reduce the computation and communication costs. A large variety of approaches for ad hoc clustering have been developed by researchers which focus on different performance metrics. This paper presents a survey of different clustering schemes.