Low-Loss N × N Wavelength Router for Efficient Switching and Multiplexing in Optical Networks

  • Bernasconi P.
  • Cappuzzo M.
  • Chen E.
  • Doerr C.
  • Dragone C.
  • Gomez L.
  • Wong-Foy A.

We demonstrate for WDM optical networks a wavelength router with substantially reduced losses using a novel waveguide grating design [1]. This technique will increase in an optical network the maximum distance that can be effectively covered by the router without amplifiers. It will also reduce, in a packet switch, the ...

XPath Satisfiability in the Presence of DTDs

  • Benedikt M.
  • Fan W.
  • Geerts F.

We study the satisfiability problem associated with XPath in the presence of DTDs. This is the problem of determining, given a query $p$ in an XPath fragment and a DTD $D$, whether or not there exists an XML document $T$ such that $T$ conforms to $D$ and the answer of ...

High-Fill-Factor Adaptive Optics Mirrors With Independent Piston, Tip, and Tilt Controls

  • Greywall D.

This paper proposes a new CCIT mirror design that utilizes shuttle-rocker-arm actuators to raise the effective pivot point of each mirror element to the midpoint of the element’s top surface. This permits a 98% fill factor. The piston, tip, and tilt degrees of freedom are independent and each can be ...

Holistic Aggregates in a Networked World: Distributed Tracking of Approximate Quantiles

  • Cormode G.
  • Garofalakis M.
  • Muthukrishnan S.
  • Rastogi R.

While traditional database systems optimize for performance on one-shot queries, emerging large-scale monitoring applications require continuous tracking of complex aggregates and data- distribution summaries over collections of physically-distributed streams. Thus, effective solutions > have to be simultaneously space efficient (at each remote site), communication efficient (across the underlying communication network), ...

3PAC: Third Party Access Control for Web Services

  • Bemmel J.
  • Lagerberg K.
  • Wegdam M.

Web Services fail to deliver on the promise of ubiquitous deployment and seamless interoperability due to the lack of a uniform, standards-based approach to all aspects of security. In particular, the enforcement of access policies in a Service Oriented Architecture is not addressed adequately. We present a novel approach to ...

Measuring Human Satisfaction in Data Networks

  • Andrews D.
  • Cao J.
  • Mcgowan Phd J.

There is currently no widely accepted method for converting packet-based measurements of Quality-of-Service (QoS) into a score reflecting a user's opinion of network performance. Such a measure is desirable for comparing networks, making design trade-offs, or enforcing service-level agreements (SLAs), and is likely to be a popular area of future ...

The most robust entangled state of light

  • Van Enk S.

We study how photon absorption losses degrade the bipartite entanglement of entangled states of light. We consider two questions: (i) what state contains the smallest average number of photons given a fixed amount of entanglement? and (ii) what state is the most robust against photon absorption? We explain why the ...

An FPGA Application with High Speed Serial Transceiver Running at Sub-nominal Rate

  • Hadzic I.
  • Suvakovic D.

We describe an implementation of the physical layer circuit for 100Mb/s optical Ethernet using an FPGA device with embedded high-speed serial transceivers. The design is the foundation for implementing a dual-speed 100/1000 Mb/s Ethernet system in which all components except the optical ones are implemented in an FPGA. Such a ...

Connectivity, Power and Energy in a Multihop Cellular Packet System

  • Avidor D.
  • Hartman K.
  • Mukherjee S.

We study large networks of subscriber stations (SSs) with certain common wireless capabilities, and base stations (BSs) having direct connection to the wired infrastructure in addition to common wireless capabilities. SS nodes can communicate with the "outside world" only through the BSs. Connections to SSs without a direct (i.e., a ...

Throughput Range Tradeoff of Wireless Mesh Backhaul Networks

  • Mukherjee S.
  • Viswanathan H.

Wireless backhaul communication is expected to play a significant role in providing the necessary backhaul resources for future high rate wireless networks. Mesh networking, in which information is routed from source to destination over multiple wireless links, has potential advantages over traditional single hop networking especially for backhaul communication. We ...

Mapweb: A Location-based Converged Communication Platform

  • Huang D.
  • Liu F.
  • Shi X.
  • Yang G.
  • Zheng L.
  • Zhou Z.

Location is valuable information in personal communication systems. Various communication mechanisms, e.g. PSTN, cellular, and soft IP phones, SMS, MMS, email, instant messaging, and real-time video streaming, are economically available today. An interesting issue is how to combine the location-based service and a variety of communications services together. We present ...

Nonlinear dynamics associated with a model of vector four-wave mixing

  • Kanaev A.
  • Kogelnik H.
  • Mckinstrie C.

The nonlinear dynamics of doubly-degenerate vector four-wave mixing (FWM) are studied analytical and numerically, in phase space and in Stokes space. Depending on the initial conditions, vector FWM can evolve aperiodically or periodically, but not chaotically. The dynamics of vector FWM are similar to, but richer than, the dynamics of ...

IRIS: An Integrated Router Interconnected Spectrally

  • Bernasconi P.
  • Duelk M.
  • Gripp J.
  • Neilson D.
  • Simsarian J.
  • Stiliadis D.
  • Winzer P.
  • Zirngibl M.

Optical switching in a load-balanced architecture can be exploited to build highly scalable packet switches. In this paper we present the architecture of the Integrated Router Interconnected Spectrally (IRIS), an all-optical router that scales to hundreds of Terabits per second. IRIS is based on a novel implementation of a load-balanced ...

Simulation and Analysis of 2.4 GHz Propagation in a Medium- Size Conference Room

  • Ling J.
  • Morgan D.

We study RF propagation in a medium-size conference room using the WiSE tool, which is a ray tracing model that has been developed for designing indoor wireless communication systems. A single specific room geometry is simulated but multiple narrowband realizations are obtained over a range of frequencies centered at 2.4 ...

WLAN Downlink Throughput Enhancement in Conference Rooms Using a Multi-Antenna Access Point

  • Morgan D.

This paper explores the enhancement of WLAN downlink throughput in a conference room environment using a multi-antenna access point. The downlink transmission uses antenna patterns to spatially separate multiple users so that they can be simultaneously served, rather than sequentially, thereby speeding up the downlink throughput. This can be useful ...

A Service Flow Management Strategy for IEEE 802.16 Broadband Wireless Access Systems in TDD Mode

  • Chen J.
  • Jiao W.
  • Wang H.

A fair and efficient service flow management architecture for IEEE802.16 Broadband Wireless Access (BWA) systems is proposed. A dynamic bandwidth allocation is proposed for TDD mode. Comparing with the traditional fixed bandwidth allocation, the proposed architecture adjusts uplink and downlink bandwidth dynamically to achieve higher throughput for unbalanced traffic. A ...

Hardness of the Undirected Congestion Minimization Problem

  • Andrews D.
  • Zhang Y.

We show that there is no $(loglog M)^{1-ve}$ approximation for the undirected congestion minimization problem unless $NP subseteq ZPTIME(n^{polylog~n})$, where $M$ is the size of the graph and $ve$ is any positive constant.

Hardness of the Undirected Edge-Disjoint Paths Problem

  • Andrews D.
  • Zhang Y.

We show that there is no $log^{{1over 3}-ve} M$ approximation for the undirected Edge-Disjoint Paths problem unless $NP subseteq ZPTIME(n^{polylog~n})$, where $M$ is the size of the graph and $ve$ is any positive constant. This hardness result also applies to the undirected All-or-Nothing Multicommodity Flow problem and the undirected Node-Disjoint ...

A Shadow-Price-Based Distributed Approach to Dynamic Load Balancing in CDMA Networks

  • Borst S.
  • Hampel K.
  • Saniee I.
  • Whiting P.

We present a linear-programming approach for dynamic load balancing in CDMA networks. The linear program characterizes the minimum achievable amplifier load for a given user configuration at each time interval, and gives a useful benchmark for the potential gains from optimizing the power assignment. The solution of the linear program ...

Novel Algorithms for Reducing Cell Sites During a Technology Upgrade and Network Overlay

  • Abusch-Magder D.

The development of newer generations of technology has created the opportunity and need for wireless providers to upgrade their networks (e.g. 2G to 3G), while market forces require them to maximize the use of their capital and preexisting investments. Upgrades in technology not only offer additional services but also performance ...