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Market-based compute grids encompass service providers offering limited resources to potential users with varying demands and willingness to pay. Providers face difficult decisions about which jobs to admit and when to schedule admitted jobs. For this
In this paper, we propose a new spatial interpolation algorithm for Intra-Frame error concealment. The method aims at interpolating areas in the image, which have been affected by packet loss. We have proposed an edge detection technique to aid the
Temporal-Angular channel sounding measurements of an indoor millimeter wave channel (60 GHz) is analyzed to determine whether ray arrivals at the receiver form clusters in the two-dimensional time-angle space. The channel behavior for directional antennas
Effective and timely link-layer trigger mechanisms can significantly influence the handover performance. The handover process will not perform the correct decision and execution unless adequate and timely link-layer trigger information is delivered. In
Using cooperative transmission, two or more single-antenna users can share their antennas to achieve spatial diversity in a slow fading channel. One relaying protocol that achieves diversity, amplify-and-forward (AF), is striking in its simplicity, but
The Domain Name System (DNS) is the global lookup service for network resources. To protect DNS information, the DNS Security Extensions (DNSSEC) has been developed and deployed on branches of the DNS to provide authentication and integrity protection
Alan Mink, Lijun Ma, Anastase Nakassis, Haolang Xu, Oliver T. Slattery, Barry J. Hershman, Xiao Tang
We have begun to expand the NIST quantum key distribution (QKD) system into a quantum network to support secure cryptography. We are starting with a simple three-node network, one Alice switched between Bob1 and Bob2. To support such a quantum network, we
Michael R. Souryal, E G. Larsson, B M. Peric, B R. Vojcic
This paper derives new soft decision metrics for coded orthogonal signaling in impulsive noise, more specifically symmetric alpha-stable noise. For the case of a known channel amplitude and known noise dispersion, exact metrics are derived both for Cauchy
This paper is mainly concerned with multi-channel transmission of real-time information such as video over multi-hop ad-hoc links. We propose two multi-channel routing protocols. The first is based on single-path routing and aims at suppressing the intra
Lijun Ma, Alan Mink, Hai Xu, Oliver T. Slattery, Xiao Tang
We demonstrate a three-node QKD network that allows multiple users to share secure keys. This QKD network operates on the 850 nm and 1550 nm wavelengths at 1.25 Gbps clock rate. The communication route is controlled by a MEMS optical switch. In this paper
Nader Moayeri, Camillo A. Gentile, Kamran Sayrafian, Michael R. Souryal
Every year a number of first responders lose their lives while battling fires or rescuing civilians during such emergencies. Indoor localization or location tracking roughly provides the same capability inside buildings that GPS does outdoors. It allows a
While the frequency-dependence of the wireless channel may be negligible for narrow to wideband signals, it has been shown that modeling this dependence for bandwidths in excess of 2 GHz improves channel reconstruction up to 40%. Yet to our knowledge, only
Vincent Gauthier, Richard A. Rouil, Nada T. Golmie
In an IEEE 802.11 network, a single user can reduce the performance of all other users attached to the same access point. To overcome this problem, we propose to take advantage of the increasing number of devices supporting multiple network interfaces. We
In this paper, a Dynamic Source Routing (DSR)-based directional routing protocol is invoked for wireless ad hoc networks using directional antennas. This is designed to balance the trade-off between co-channel interferences from nodes hops away, and the
Effective and timely link layer trigger mechanisms can significantly influence the handover performance. In this paper, a predictive link trigger mechanism for seamless horizontal and vertical handovers in heterogeneous wireless networks is proposed
Flow-level performance of fair bandwidth sharing protocols under random flow arrivals/departures is not sufficiently understood due to intractability of the corresponding Markov model for realistic-size networks. Tractability of the Markov model in fluid
A flow-level Markov model for fair bandwidth sharing with packet retransmissions under random flow arrivals/departures is proposed and discussed. Fluctuations in the numbers of flows in progress cause the network instability even under light load. The
Behnam Neekzad, Kamran Sayrafian, Julio Perez, John Baras
Temporal-Angular channel sounding measurements of an indoor millimeter wave channel (60 GHz) is analyzed to determine the location of two dimensional clusters of arrivals at the receiver. The measurement scenarios are also emulated by a ray tracing tool
The National Institute of Standards and Technology (NIST) high-speed quantum key distribution (QKD) system was designed to include custom hardware to support the generation and management of gigabit data streams. As our photonics improved our software
A simple technique to estimate the position of a mobile node inside a building is based on the Received Signal Strength (RSS). In a previous publication, we investigated the feasibility of using circular array antennas and beamforming in order to enable an
A flow-level Markov model for fair bandwidth sharing with packet retransmissions and random flow arrivals/departures is proposed. The model accounts for retransmissions by assuming that file transfer rates are determined by the end-to-end goodputs rather
D. Richard Kuhn, Kotikalapudi Sriram, Douglas Montgomery
This document introduces the Border Gateway Protocol (BGP), explains its importance to the internet, and provides a set of best practices that can help in protecting BGP. Best practices described here are intended to be implementable on nearly all
RF-based indoor positioning is a challenging task due to the harsh indoor propagation environment. Techniques based on the received signal strength are simple to implement and offer low cost and effective alternatives for some applications. The main
The falling price and reduced size of sensors for monitoring spatially-sensitive environmental properties such as temperature, light, sound, and vibration have motivated research in location algorithms in recent years. To our knowledge, the algorithm which