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A Mobile Ad hoc Network (MANET) is a set of mobile wireless devices, which communicate by forwarding packets for each other. These autonomous devices act as routers and as end nodes as well. The communication from one node to another can happen in many routes with different number of hops. Because of mobility these routes change dynamically. Recent application of MANETs have strong Quality of Service...
This paper provides an overview of reputation-based approaches aiming to enhance trusted functionality in ad hoc distributed resource-sharing networks. More specifically, it focuses on three essential functions, namely, secure routing, secure resource management and trusted service composition. We first note the necessity to use reputation and trust to establish safe and efficient collaboration in...
We consider the problem of content distribution to a group of cooperative wireless peer devices that desire the same block of information. The QoS metric is that peers are all required to receive the block by a fixed deadline, with a certain target probability. The block is divided into chunks, which are received via two methods that can be used simultaneously — (i) the B2P (base-station-to-peer)...
In this paper, we investigate the impact of relay cooperation for maintaining coverage area against aggregate interference from incumbent underlaid interferers. We employ a guard zone for uplink so that non-urgent interferers are inhibited and urgent ones are admitted with a controlled access probability as long as the primary receiver can tolerate. Numerical results show the outage probability of...
Overlay networks based on the P2P paradigm have been successfully employed to facilitate reliable data transport. They are used to improve the dependability of traffic flows between end-hosts without changing the underlying infrastructure. By observing connections between neighbours, the overlay can predict the statistical behaviour of the network and can thus select proper routes. In particular,...
Wireless sensor and actor networks (WSANs) can be used for monitoring physical environments and acting according to the observations. In order to differentiate the actions based on the sensed information, WSANs comprise of various applications with different quality of service (QoS) requirements. QoS solutions for WSANs are challenging compared to traditional networks because of the limited resource...
Ad Hoc networks are characterized as fast time-varying. Thus, fast distributed algorithm to implement self-management is indispensable, especially for QoS support. In this paper, we propose rate control with QoS support in Ad Hoc networks based on primal-dual interior-point method. We apply Gaussian belief propagation algorithm to compute the Newton step. For implementing distributed computation in...
A novel cluster-head selection and update algorithm "Type-based Cluster-forming Algorithm (TCA)" is proposed, which outperforms both the lowest node ID (LID) and the Weighted Clustering Algorithm (WCA) in the ad hoc network scenario considered. The system's performance is investigated in a scenario, when the 50 communicating nodes belong to three different groups, for example, a group of...
This article presents a new MAC layer protocol for IEEE 802.11 EDCA-based ad-hoc networks with hidden nodes. The key idea of the proposed solution is based on an intelligent two-step reservation procedure which is combined with the advantages of EDCA service differentiation. The new protocol achieves significant performance improvement for high priority traffic (e.g., Voice) in terms of fairness,...
In this paper, we consider the joint problem of congestion control and scheduling with multi-class Quality of Service (QoS) requirements. Generally, the joint problem is formulated as a Network Utility Maximization (NUM) problem and can be decomposed into a congestion control problem and a scheduling problem. Usually, the congestion control problem can be solved in a distributed manner by tracking...
Existing studies on the design of routing protocols for wireless ad hoc networks mainly focused on energy efficiency. However, in many real-time applications such as target tracking and bush fire surveillance, latency is an important concern, and little attention has been paid to it in the design of routing protocols for such applications to meet the specified Quality of Service (QoS) requirements...
The area of mobile ad hoc networking has gained widespread interest of the network research community in recent years because of the ability of the MANETs to provide truly distributed and decentralized communication facility on ad hoc basis. But due to the bandwidth constrained links and limited transmission range of the mobile nodes, MANETs suffer from the inability to cover a wider network area...
Admission and rate control are key components for providing QoS (Quality of Service) flows in multi- rate wireless ad hoc networks where transmission rate at the physical layer is adapted dynamically according to the channel condition. Key to these controls is the formulation of a rate constraint that can regulate the flow rate passing through each node. This paper formulates a cross-layer rate constraint...
Several routing protocols for mobile ad hoc networks work efficiently only in bidirectional networks. Unidirectional links may exist in a real network due to variation in transmission power of different nodes, noise or other signal propagation phenomena, and heterogeneity in transmission hardware of nodes in the network. We introduce a sub-layer called Modified AODV (ad-hoc on demand distance vector)...
The proliferation of networked appliances or dedicated function consumer devices with embedded processors and network connection capabilities is driving the virtual device concept, whereby such appliances can be controlled, monitored, managed, and extended beyond what they were initially designed to do. The dynamic and ad hoc nature of the discovery and composition of such devices and the services...
An admission control Algorithm must organize among flows and should afford assurance of how the medium is shared between nodes. In a wired network, nodes can keep an eye on the medium to see how much bandwidth is being used by the network. On the other hand, in an Ad-Hoc network, during communication nodes possibly will use the bandwidth of neighbouring nodes. Consequently, the bandwidth consumption...
Currently there are a range of digital devices and the trend is moving us closer to an increasingly interconnected world. However one of the current limitations is that device usage is location dependent. For example, when you are in your home environment and your PDA, which contains MP3s, resides in your work environment, there is no mechanism to enable you to use the functionality it provides. Mechanisms...
IEEE 802.15.4 is the emerging next generation wireless standard designed for low-rate wireless personal area networks (LR-WPAN), which suit wireless sensor networks applications. It attempts to provide a low cost, low power and short range wireless networking. The QoS is more challenging in heterogeneous wireless sensors networks, where a diverse mixture of sensors for monitoring temperature, pressure,...
In this paper, we study a cognitive coexistence strategy for heterogeneous networks. While a lot of previous works focused on spectrum underlay approaches for weak interference scenarios, a high power infrastructure (IS) transmitter creates a large dead zone for nearby ad-hoc (AH) links using the same spectrum. To address this problem, we propose to utilize a half-duplex decode-and-forward (DF) relay...
In order to achieve cooperative driving in vehicular ad hoc networks (VANET), broadcast transmission is usually used for disseminating safety-related information among vehicles. Nevertheless, broadcast over multihop wireless networks poses many challenges due to link unreliability, hidden terminal, message redundancy, and broadcast storm, etc., which greatly degrade the network performance. In this...
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