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.

Ad hoc-VCG: a truthful and cost-efficient routing protocol for mobile ad hoc networks with selfish agents

Abstract: We introduce a game-theoretic setting for routing in a mobile ad hoc network that consists of greedy, selfish agents who accept payments for forwarding data for other agents if the payments cover their individual costs incurred by forwarding data. In this setting, we propose Ad hoc-VCG, a reactive routing protocol that achieves the design objectives of truthfulness (i.e., it is in the agents' best interest to reveal their true costs for forwarding data) and cost-efficiency (i.e., it guarantees that routing is done along the most cost-efficient path) in a game-theoretic sense by paying to the intermediate nodes a premium over their actual costs for forwarding data packets. We show that the total overpayment (i.e., the sum of all premiums paid) is relatively small by giving a theoretical upper bound and by providing experimental evidence. Our routing protocol implements a variation of the well-known mechanism by Vickrey, Clarke, and Groves in a mobile network setting. Finally, we analyze a very natural routing protocol that is an adaptation of the Packet Purse Model [8] with auctions in our setting and show that, unfortunately, it does not achieve cost-efficiency or truthfulness.

Time synchronization in ad hoc networks

Abstract: Ubiquitous computing environments are typically based upon ad hoc networks of mobile computing devices. These devices may be equipped with sensor hardware to sense the physical environment and may be attached to real world artifacts to form so-called smart things. The data sensed by various smart things can then be combined to derive knowledge about the environment, which in turn enables the smart things to "react" intelligently to their environment. For this so-called sensor fusion, temporal relationships (X happened before Y) and real-time issues (X and Y happended within a certain time interval) play an important role. Thus physical time and clock synchronization are crucial in such environments. However, due to the characteristics of sparse ad hoc networks, classical clock synchronization algorithms are not applicable in this setting. We present a time synchronization scheme that is appropriate for sparse ad hoc networks

GPS-free Positioning in Mobile Ad Hoc Networks

Abstract: We consider the problem of node positioning in ad hoc networks. We propose a distributed, infrastructure-free positioning algorithm that does not rely on GPS (Global Positioning System). Instead, the algorithm uses the distances between the nodes to build a relative coordinate system in which the node positions are computed in two dimensions. Despite the distance measurement errors and the motion of the nodes, the algorithm provides sufficient location information and accuracy to support basic network functions. Examples of applications where this algorithm can be used include Location Aided Routing [10] and Geodesic Packet Forwarding [2]. Another example are sensor networks, where mobility is less of a problem. The main contribution of this work is to define and compute relative positions of the nodes in an ad hoc network without using GPS. We further explain how the proposed approach can be applied to wide area ad hoc networks.

Secure Routing for Mobile Ad Hoc Networks

Abstract: The emergence of the Mobile Ad Hoc Networking (MANET) technology advocates self-organized wireless interconnection of communication devices that would either extend or operate in concert with the w ...

On the capacity improvement of ad hoc wireless networks using directional antennas

Abstract: The capacity of ad hoc wireless networks is constrained by the interference between concurrent transmissions from neighboring nodes. Gupta and Kumar have shown that the capacity of an ad hoc network does not scale well with the increasing number of nodes in the system when using omnidirectional antennas [6]. We investigate the capacity of ad hoc wireless networks using directional antennas. In this work, we consider arbitrary networks and random networks where nodes are assumed to be static.In arbitrary networks, due to the reduction of the interference area, the capacity gain is proven to be √2π/α when using directional transmission and omni reception. Because of the reduced probability of two neighbors pointing to each other, the capacity gain is √2π/β when omni transmission and directional reception are used. Although these two expressions look similar, the proof technique is different. By taking advantage of the above two approaches, the capacity gain is 2π/√αβ when both transmission and reception are directional.For random networks, interfering neighbors are reduced due to the decrease of interference area when directional antennas are used for transmission and/or reception. The throughput improvement factor is 2π/α, 2π/β and 4π2/αβ for directional transmission/omni reception, omni transmission/direc-tional reception, and directional transmission/directional reception, respectively.We have also analyzed hybrid beamform patterns that are a mix of omnidirectional/directional and a better model of real directional antennas.