Tracking Message Spread in Mobile Delay Tolerant Networks

Tracking Message Spread in Mobile Delay Tolerant Networks Delay Tolerant Network is considered under two message forwarding schemes – a non-replicative direct delivery scheme and a replicative epidemic routing scheme. The objective is to track the degree of spread of a message in the network. Such estimation can be used for on-line control of message dissemination. With a homogeneous mobility model with pairwise i.i.d. exponential intermeeting times, we rigorously derive the system dynamic and measurement equations for optimal tracking by a Kalman filter. Moreover, we provide a framework for tracking…

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A Privacy-Preserving Framework for Managing Mobile Ad Requests and Billing Information

A Privacy-Preserving Framework for Managing Mobile Ad Requests and Billing Information Organizations are starting to realize the significant value of advertising on mobile devices, and a number of systems have been developed to exploit this opportunity. From a privacy perspective, practically all systems developed so far are based either on a trusted third-party model or on a generalized architecture. A system proposed for delivering context, location, time, and preference-aware advertisements to mobiles with a novel architecture to preserve privacy. The main adversary in this model is the server distributing the…

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Privacy-Preserving and Truthful Detection of Packet Dropping Attacks in Wireless Ad Hoc Networks

Privacy-Preserving and Truthful Detection of Packet Dropping Attacks in Wireless Ad Hoc Networks Mobile Computing Link error and malicious packet dropping are two sources for packet losses in multi-hop wireless ad hoc network. In this paper, while observing a sequence of packet losses in the network, we are interested in determining whether the losses are caused by link errors only, or by the combined effect of link errors and malicious drop. We are especially interested in the insider-attack case, whereby malicious nodes that are part of the route exploit their…

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Cooperative Caching for Efficient Data Access in Disruption Tolerant Networks

Cooperative Caching for Efficient Data Access in Disruption Tolerant Networks Disruption tolerant networks (DTNs) are characterized by low node density, unpredictable node mobility, and lack of global network information. Most of current research efforts in DTNs focus on data forwarding, but only limited work has been done on providing efficient data access to mobile users. A novel approach is proposed to support cooperative caching in DTNs, which enables the sharing and coordination of cached data among multiple nodes and reduces data access delay. The basic idea is to intentionally cache…

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Energy-optimum Throughput and Carrier Sensing Rate in CSMA-based Wireless Networks

Energy-optimum Throughput and Carrier Sensing Rate in CSMA-based Wireless Networks A model for the energy consumption of a node as a function of its throughput in a wireless CSMA network is proposed. A single-hop network is modeled, and then a multi-hop network. The operating the CSMA network at a high throughput is energy inefficient since unsuccessful carrier sensing attempts increase the energy consumption per transmitted bit. Operating the network at a low throughput also causes energy inefficiency because of increased sleeping duration. Achieving a balance between these two opposite operating…

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Video Dissemination over Hybrid Cellular and Ad Hoc Networks

Video Dissemination over Hybrid Cellular and Ad Hoc Networks We study the problem of disseminating videos to mobile users by using a hybrid cellular and ad hoc network. In particular, we formulate the problem of optimally choosing the mobile devices that will serve as gateways from the cellular to the ad hoc network, the ad hoc routes from the gateways to individual devices, and the layers to deliver on these ad hoc routes. We develop a Mixed Integer Linear Program (MILP)-based algorithm, called POPT, to solve this optimization problem. We…

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Discovery and Verification of Neighbor Positions in Mobile Ad Hoc Networks

Discovery and Verification of Neighbor Positions in Mobile Ad Hoc Networks MOBILE COMPUTING, FEBRUARY 2013 Technology Implementation: JAVA A growing number of ad hoc networking protocols and location-aware services require that mobile nodes learn the position of their neighbors. However, such a process can be easily abused or disrupted by adversarial nodes. In absence of a priori trusted nodes, the discovery and verification of neighbor positions presents challenges that have been scarcely investigated in the literature. In this paper, we address this open issue by proposing a fully distributed cooperative…

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Distributed resource allocation for multi-cell relay-aided OFDMA systems

Distributed resource allocation for multi-cell relay-aided OFDMA systems Technology Used: Java An efficient resource allocation (RA) scheme is proposed for downlink of relay-aided orthogonal frequency division multiple access systems. To mitigate excessive computational complexity of the centralized RA where the base station (BS) is responsible for resource allocation of the entire cell, a distributed RA strategy is taken with which each relay station (RS) and BS perform resource allocation for their respective receivers by themselves. The proposed RA scheme is composed of two parts, RS resource allocation (RS-RA) and BS…

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Optimal content downloading in vehicular networks

Optimal content downloading in vehicular networks Consider a system where users aboard communication-enabled vehicles are interested in downloading different contents from Internet-based servers. This scenario captures many of the infotainment services that vehicular communication is envisioned to enable, including news reporting, navigation maps and software updating, or multimedia file downloading. In this paper, we outline the performance limits of such a vehicular content downloading system by modeling the downloading process as an optimization problem, and maximizing the overall system throughput. Our approach allows us to investigate the impact of different…

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Optimal Multicast Capacity and Delay Tradeoffs in MANETs

Optimal Multicast Capacity and Delay Tradeoffs in MANETs Feb 2013 In this paper, we give a global perspective of multicast capacity and delay analysis in Mobile Ad-hoc Networks (MANETs). Specifically, we consider four node mobility models: (1) two-dimensional i.i.d. mobility, (2) two-dimensional hybrid random walk, (3) one-dimensional i.i.d. mobility, and (4) one-dimensional hybrid random walk. Two mobility time-scales are included in this paper: (i) Fast mobility where node mobility is at the same time-scale as data transmissions; (ii) Slow mobility where node mobility is assumed to occur at a much…

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