Showing papers on "Testbed published in 1998"

The Globus project: a status report

Abstract: The Globus project is a multi-institutional research effort that seeks to enable the construction of computational grids providing pervasive, dependable, and consistent access to high-performance computational resources, despite geographical distribution of both resources and users. Computational grid technology is being viewed as a critical element of future high-performance computing environments that will enable entirely new classes of computation-oriented applications, much as the World Wide Web fostered the development of new classes of information-oriented applications. The authors report on the status of the Globus project as of early 1998. They describe the progress that has been achieved to date in the development of the Globus toolkit, a set of core services for constructing grid tools and applications. They also discuss the Globus Ubiquitous Supercomputing Testbed (GUSTO) that they have constructed to enable large-scale evaluation of Globus technologies, and they review early experiences with the development of large-scale grid applications on the GUSTO testbed.

Transparent optical packet switching: network architecture and demonstrators in the KEOPS project

Abstract: This paper reviews the work carried out in the ACTS KEOPS (Keys to Optical Packet Switching) project, describing the results obtained to date. The main objective of the project is the definition, development, and assessment of optical packet switching and routing networks, capable of providing transparency to the payload bit rate, using optical packets of fixed duration and low bit rate headers in order to enable easier processing at the network/node interfaces. The feasibility of the KEOPS concept is assessed by modeling, laboratory experiments, and testbed implementation of optical packet switching nodes and network/node interfacing blocks, including a fully equipped demonstrator. The demonstration relies on advanced optoelectronic components, developed within the project, which are described.

A fault detection service for wide area distributed computations

Abstract: The potential for faults in distributed computing systems is a significant complicating factor for application developers. While a variety of techniques exist for detecting and correcting faults, the implementation of these techniques in a particular context can be difficult. Hence, we propose a fault detection service designed to be incorporated, in a modular fashion, into distributed computing systems, tools, or applications. This service uses well-known techniques based on unreliable fault detectors to detect and report component failure, while allowing the user to tradeoff timeliness of reporting against false positive rates. We describe the architecture of this service, report on experimental results that quantify its cost and accuracy, and describe its use in two applications, monitoring the status of system components of the GUSTO computational grid testbed and as part of the NetSolve network-enabled numerical solver.

Player for adaptive MPEG video streaming over the Internet

Abstract: This paper describes the design and implementation of a real-time, streaming, Internet video and audio player. The player has a number of advanced features including dynamic adaptation to changes in available bandwidth, latency and latency variation; a multi-dimensional media scaling capability driven by user-specified quality of service (QoS) requirements; and support for complex content comprising multiple synchronized video and audio streams. The player was developed as part of the QUASAR project at Oregon Graduate Institute, is freely available, and serves as a testbed for research in adaptive resource management and QoS control.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Intelligent multi-shot visualization interfaces for dynamic 3D worlds

Abstract: In next-generation virtual 3D simulation, training, and entertainment environments, intelligent visualization interfaces must respond to user-specified viewing requests so users can follow salient points of the action and monitor the relative locations of objects. Users should be able to indicate which object(s) to view, how each should be viewed, cinematic style and pace, and how to respond when a single satisfactory view is not possible. When constraints fail, weak constraints can be relaxed or multi-shot solutions can be displayed in sequence or as composite shots with simultaneous viewports. To address these issues, we have developed CONSTRAINTCAM, a real-time camera visualization interface for dynamic 3D worlds. It has been studied in an interactive testbed in which users can issue viewing goals to monitor multiple autonomous characters navigating through a virtual cityscape. CONSTRAINTCAM’s real-time performance in this testbed is encouraging.

Evaluating database selection techniques: a testbed and experiment

Abstract: We describe a testbed for database selection techniques and an experiment conducted using this testbed. The testbed is a decomposition of the TREC/TIPSTER data that allows analysis of the data along multiple dimensions, including collection-based and temporal-based analysis. We characterize the subcollections in this testbed in terms of number of documents, queries against which the document,s have been evaluated for relevance, and distribution of relevant documents. We then present initial results from a study conducted using this testbed that examines the effectiveness of the gGlOSS approach to database selection. The databases from our testbed were ranked using the gGl0S.S techniques and compared to the gGlOSS I&l(l) baseline and a baseline derived from TREC relevance judgements. We have examined the degree to which several gGlOSS estimate functions approximate these baselines. Our initial results confirm that the gGZOSS estimators are excellent predictors of the Ideal(Z) ranks but that the Ideal(l) ranks do not estimate relevance-based ranks well.

Experimental implementation of integrator backstepping and passive nonlinear controllers on the RTAC testbed

Abstract: This paper fully describes the RTAC experimental testbed which provides a means for implementing and evaluating nonlinear controllers. The description of the testbed includes all physical parameters of the device that are relevant to the design and implementation of controllers. Next, four nonlinear controllers are considered. The first controller is a static, full-state-feedback, globally asymptotically stabilizing control law developed using partial feedback linearization and integrator backstepping. Next, three nonlinear controllers based upon passivity principles are presented, two of which are encompassed by the classical passivity framework, while the third is based upon the novel concept of virtual resetting absorbers. The passive controllers do not require either translational position or velocity measurements. All of the controllers are implemented on the RTAC testbed and their performance is examined. © 1998 John Wiley & Sons, Ltd.

Visualization Space: A Testbed for Deviceless Multimodal User Interface

Abstract: The Visualization Space ("VizSpace") is a visual computing system created as a testbed for deviceless multimodal user interfaces. Continuous voice recognition and passive machine vision provide two channels of interaction with computer graphics imagery on a wall-sized display. Users gesture (e.g., point) and speak commands to manipulate and navigate through virtual objects and worlds. Voiced commands are combined with several types of gestures-fullbody, deictic, symbolic and iconic- to allow users to interact using only these natural human-to-human communication skills. The system is implemented on a single (high-end) IBM PC, yet provides comfortably interactive rates. It allows for rapid testing of voice/vision multimodal input and rapid prototyping of specific multimodal applications for natural interaction.

Smart Antenna Systems and Wireless LANs

Abstract: This book covers the design and mechanics of smart antenna systems and their compatibility with the worldwide wireless LAN standard (IEEE 802.11). Included are applications for Wireless LANs, terrestrial and satellite cellular systems, wireless data distribution systems, and other advanced systems. In-depth coverage is provided on utilizing smart antenna systems to increase network capacity, reduce the effects of channel fading, extend antenna battery life, and enhance the range of any wireless communications systems. The author has also included a wide range of testbed experimental results on diversity gain, LEO Iridium-like satellite emulation, as well as other advanced topics such as MAC and PHY layers, dynamic slot assignment, timing synchronization, and spatial signature properties of a smart antenna system. Many of these topics are being presented for the first time in an organized, readable book form. Smart Antenna Systems and Wireless LANs is a timely book for designers, engineers, and researchers of wireless communications systems.

The CoVis Project: Building a Large-Scale Science Education Testbed'$

Abstract: This paper describes the construction and research program of the Learning Through Collaborative Visualization (CoVis) Project, a testbed for exploring science education reform with telecommunications technology. The CoVis testbed is contrasted with other forms of educational research in an “ecology of paradigms,” which argues that testbeds are in fact a new setting for research with different requirements and challenges for the researcher. Two extended examples of telecommunications research are provided as examples of the kind of research that testbeds are well suited to explore. The first example is the evolution of videoconferencing in the CoVis testbed. The second example is the design and development of a networked groupware application called the Collaboratory Notebook.

Experiences with a Mobile Testbed

Abstract: This paper presents results from an eight-day network packet-trace of MosquitoNet. MosquitoNet allows users of laptop computers to switch seamlessly between a metropolitan-area wireless network and a wired network (10 Mbit/s Ethernet) available in offices and on-campus residences. Results include the amount of user mobility between the wired and wireless networks, the amount of mobility within the wireless network, an examination of application end-to-end delays, and an examination of overall packet loss and reordering in the wireless network. We find that the average mobile host switches between the wired and wireless networks 14 times during the trace and moves within the wireless network five times. Round trip latencies in the wireless network are very high, with a minimum of 0.2 seconds. Even higher end-to-end delays, of up to hundreds of seconds, are due to packet loss and reordering. These delays cause users to change their usage patterns when connected to the wireless network. We conclude that latency is a critical problem in the wireless network.

Soldier Phone: an innovative approach to wireless multimedia communications

Abstract: A number of tactical military and commercial applications require multimedia, self-organizing, high throughput, wireless networks that can operate independently of fixed or external infrastructures. These uses range from low echelon push-to-talk radio to higher echelon subscriber access to MSE, and include commercial applications such as wireless LANs and emergency communications. The Soldier Phone system addresses these needs with an innovative concept termed orthogonal domain multiple access (ODMA) to provide dynamic bandwidth management. It adjusts radio transmit and receive times, channels, and data rates to match the dynamic radio frequency (RF) environment and user traffic loading. ODMA is embedded in a larger suite of protocols that manage the peer-to-peer communications. These include ATM style switching for datagrams and virtual circuits; network management for routing, signaling, and address resolution; and user convergence for many traffic types. This protocol suite has been integrated with baseband digital signal processing (DSP) functions to yield a wireless networking engine (WNE). Soldier Phone is the first instantiation of the WNE and has been successfully demonstrated in a laboratory testbed.

Poker as Testbed for AI Research

Abstract: For years, games researchers have used chess, checkers and other board games as a testbed for artificial intelligence research. The success of world-championship-caliber programs for these games has resulted in a number of interesting games being overlooked. Specifically, we show that poker can serve as an interesting testbed for machine intelligence research related to decision making problems. Poker is a game of imperfect knowledge, where multiple competing agents must deal with risk management, agent modeling, unreliable information and deception, much like decision-making applications in the real world. The heuristic search and evaluation methods successfully employed in chess are not helpful here. This paper outlines the difficulty of playing strong poker, and describes our first steps towards building a world-class poker-playing program.

Supporting adaptive video applications in mobile environments

Abstract: The transmission of digital video over wireless networks is becoming a reality: it is now possible to construct working prototype systems which illustrate the benefits to be accrued from the integration of mobile computing and digital video. However, systems which deploy video in mobile environments must be able to adapt to changes in the quality of service of their underlying communications channel. The authors focus on the practical applications and implications of supporting adaptive video in mobile environments. In particular, we describe a testbed which supports multicast transmission of stored and live video sequences over both WaveLAN and GSM technologies. The testbed employs H.263 and MPEG encoding techniques and enables clients to freely roam between heterogeneous networks while maintaining video connectivity.

Virtual InterNetwork Testbed: Status and Research Agenda

Abstract: Simulation is an important tool in network protocol development, providing an e ective way to perform controlled experiments, consider alternative designs, understand protocol interactions, and examine scales and topologies that are di cult to create in the laboratory. However, the scale and heterogeneity of today's networks create challenges for network simulation. In particular, con guring simulation inputs, properly modeling the myriad of interacting protocols, and processing and visualizing simulation output is becoming increasing di cult. The VINT project is developing a set of tools centered around ns simulator and nam network animator to meet these challenges. This paper describes the current status and future directions of this ongoing work.

The MONET New Jersey network demonstration

Abstract: The multiwavelength optical networking (MONET) consortium has demonstrated national-scale optical networking in a multilocation testbed in New Jersey. The demonstration involves transparent optical connections over path lengths as long as 2290 km, through several network elements (NEs) controlled by two interoperating network control and management (NC&M) systems. This paper describes in detail the three constituent testbeds and the experiments.

The Illinois Roadway Simulator-a hardware-in-the-loop testbed for vehicle dynamics and control

Abstract: The Illinois Roadway Simulator (IRS) is a novel, hardware-in-the-loop (HIL) scale vehicle testbed used to study vehicle dynamics and controls. An overview of this system is presented, and individual hardware issues are addressed. System modeling results on the vehicles and hardware are introduced, and comparisons of the resulting dynamics are made with full sized vehicles. To address the realism factor of using scaled vehicles, comparisons are made between vehicle responses of full and 1:10 scale vehicles. Finally, the IRS is used to examine the effect of actuator dynamics on a particular vehicle control application.

WiPPET, a virtual testbed for parallel simulations of wireless networks

Abstract: We describe the TED/C++ implementation of WIPPET, a parallel simulation testbed for evaluating radio resource management algorithms and wireless transport protocols. Versions 0.3 and 0.4 of the testbed model radio propagation (long- and short-scale fading and interference) and protocols for integrated radio resource management in mobile wireless voice networks including the standards based AMPS, NA-TDMA and GSM protocols, and several research oriented protocol families. We provide parallel performance data verifying that the dominant computational demand due to received signal quality calculation can be partitioned geographically by orthogonal radio channels, or in a hybrid manner.

Poker as a Testbed for Machine Intelligence Research

Abstract: For years, games researchers have used chess, check ers and other board games as a testbed for machine intelligence research. The success of world-champio nship-caliber programs for these games has resulted in a number of interesting games being overlooked. Specifically, we show that poker can serve as a better testbed for machine intelligence research re lated to decision making problems. Poker is a game of imperfect knowledge, where multiple competing agents must deal with risk management, agent modeling, unreliable information and deception, much like decision-making applications in the real world. The heuristic search and evaluation methods successfully employed in chess are not helpful here . This paper outlines the difficulty of playing stron g poker, and describes our first steps towards buil ding a world-class poker-playing program.

ENDE: an End-to-end Network Delay Emulator

Abstract: The Internet provides a common interface between ographics. different types of computers and networks, and various applications and protocols are constantly being developed. A new protocol or application after being developed has to be tested on the real Internet or simulated on a testbed for debugging and performance evaluation. protocol developer typically requires access to multiple machines across the Internet for this reason. In this thesis we present a new took that can emulate end-to-end delays between two hosts without requiring access to the second host. The tool enables the user to test new protocols realistically on a single machine. The tool observes network status on a particular path using ICMP packets and uses it as a real-time traffic source. Experimented results are presented to show that this approach is effective and quite accurate.

Internet-based web-mediated collaborative design and learning environment

Abstract: This paper presents an overview of an on-going effort that focuses on combined research and curriculum development. It presents a tool kit of collaboration technologies developed by our group, and an education testbed for multidisciplinary and geographically distributed teams that exercise the Internet-based Web-mediated collaborative technologies tool kit. The tool kit of collaboration technologies is aimed to assist team members, project managers and owners to: (1) capture, share, publish, and link knowledge and information related to a specific project, (2) navigate through the archived knowledge and information, (3) evaluate and explain the product's performance, and (4) interact in a timely fashion. The Architecture/Engineering/Construction (AEC) course offered at Stanford University acts as a testbed for cutting edge information technologies and a forum that trains a new generation of professionals to team up with practitioners from other disciplines and take advantage of information technology to produce a better, faster, cheaper product. The paper concludes with a number of questions regarding the impact of information technologies on team performance and behavior.

3D reconstruction of environments for virtual collaboration

Abstract: In this paper we address an application of computer vision which can in the future change completely our way of communicating over the network. We present our version of a testbed for telecollaboration. It is based on a highly accurate and precise stereo algorithm. The results demonstrate the live (on-line) recovery of 3D models of a dynamically changing environment and the simultaneous display and manipulation of the models.

Learning Communication Strategies in Multiagent Systems

Abstract: In this paper we describe a dynamic, adaptive communication strategy for multiagent systems. We discuss the behavioral parameters of each agent that need to be computed, and provide a quantitative solution to the problem of controlling these parameters. We also describe the testbed we built and the experiments we performed to evaluate the effectiveness of our methodology. Several experiments using varying populations and varying organizations of agents were performed and are reported. A number of performance measurements were collected as each experiment was performed so the effectiveness of the adaptive communications strategy could be measured quantitatively. The adaptive communications strategy proved effective for fully connected networks of agents. The performance of these experiments improved for larger populations of agents and even approached optimal performance levels. Experiments with non-fully connected networks showed that the adaptive communications strategy is extremely effective, but does not approach optimality. Other experiments investigated the ability of the adaptive communications strategy to compensate for “distracting” agents, for systems where agents are required to assume the role of information routers, and for systems that must decide between routing paths based on cost information.

A common multi-agent testbed for diverse seamless personal information networking applications

Abstract: This article describes the design and implementation of a unique cooperative agents testbed aimed at addressing diverse applications for the difficult problem of seamless personal information networking (SPIN). The real-world SPIN testbed is aimed at two difficult applications. Namely seamless messaging and intelligent network management. Both applications are agent-driven and share agent behavior, and the messaging agents rely on the network management device diagnostic agents for input. The article introduces both problem areas in a common testbed. The first-generation seamless messaging application is described in detail. User-centric seamless messaging assumes heterogeneous communication environments intended to support today's nomadic users. The prototype is introduced for the management of messages across distributed information networks. Its aim is to intercept, filter, interpret, and deliver multimodal messages, be they voice, fax, video, and/or e-mail messages. A user's personal communication agent is charged with delivering messages to the recipient regardless of their target messaging device-a telephone, pager, desktop, wireless laptop, or wireless phone. Personal communication agents classify and act on incoming messages based on their content. A secretary agent routes and tailors urgent messages appropriately to the device manager agent, which delivers the message to a device on which the user may be roaming or active. What makes the seamless messaging application unique is its approach to treating a message in a universal manner, and its ability to mediate between different messaging environments and devices, and to try to track and find the user.

An experimental architecture for providing QoS guarantees in mobile networks using RSVP

Abstract: Efforts are underway to enhance the Internet with quality of service (QoS) capabilities for transporting real-time data. The ReSerVation Protocol (RSVP) provides a signaling mechanism for end-to-end QoS negotiation. The issue of wireless networks and mobile hosts being able to support applications that require QoS has become very significant. Reservation of resources and the maintenance of QoS for the mobile as it moves from one region to another creates a new set of challenges. We describe an architecture where a modified RSVP protocol helps provide QoS support for mobile hosts. The modified RSVP protocol has been implemented in an experimental wireless and mobile testbed to study the feasibility of our approach.

High-speed wide area, data intensive computing: a Ten Year Retrospective - eScholarship

Abstract: 7th IEEE Symposium on High Performance Distributed Computing, July 29-31, 1998, Chicago, Ill. High-Speed, Wide Area, Data Intensive Computing: A Ten Year Retrospective 1 William E. Johnston Information and Computing Sciences Division, Lawrence Berkeley National Laboratory Berkeley, CA, 94720 Abstract Modern scientific computing involves organizing, moving, visualizing, and analyzing massive amounts of data from around the world, as well as employing large- scale computation. The distributed systems that solve large-scale problems will always involve aggregating and scheduling many resources. Data must be located and staged, cache and network capacity must be available at the same time as computing capacity, etc. Every aspect of such a system is dynamic: locating and scheduling resources, adapting running application systems to availability and congestion in the middleware and infrastructure, responding to human interaction, etc. The technologies, the middleware services, and the architectures that are used to build useful high-speed, wide area distributed systems, constitute the field of data intensive computing. This paper explores some of the history and future directions of that field. This is not a comprehensive review of the field, though I have been involved in many of the seminal activities. I will acknowledge a number of people in the course of this article, but there will be those whose important contributions did not directly intersect our work, and whom I will therefore not mention. The body of this paper is organized into three major sections: where are we today, how did we get there, and where are we going in the future. 2. Where Are We Today? As a precursor to routine remote high-speed access to large-scale mass storage systems, a recent set of experiments were conducted between Lawrence Berkeley National Laboratory (LBNL) in Berkeley, Calif., and the Stanford Linear Accelerator (SLAC) in Palo Alto, Calif. The National Transparent Optical Network testbed (NTON - see [1]) testbed provides eight 2.4 gigabit/sec data channels around the San Francisco Bay, of which four are usually used for OC-48 SONET. For this experiment, the network configuration involved four to six ATM switches and a Sun Enterprise-4000 SMP as a data receiver at 1. Introduction This paper is a personal view of the evolution of data intensive computing over the past ten years. The evolution is traced through a series of milestones that are based on advances in the technology, architectures, and software, and that have brought us from the point when we were lucky to get a few hundred kilobits/second of application-to-application data on a local area network, to the current time, where we can routinely get almost 500 megabits/second on wide area networks. The work described in this paper is supported by the U. S. Dept. of Energy, Office of Energy Research, Office of Computational and Technology Research, Mathematical, Information, and Computational Sciences and ERLTT Divisions under contract DE-AC03- 76SF00098 with the University of California, and by DARPA, Information Technology Office. This is report no. LBNL-41862. wejohnston@lbl.gov, www-itg.lbl.gov/~johnston © IEEE Figure 1 Where we are now. TenYearRetrospective.IEEE2col.fm- 5/28/00 - 1

Design and development of a legged robot research platform JROB-1

Abstract: A legged robot "JROB-1" is developed for a robotics research platform as a result of inter-university research program on intelligent robotics supported by the Ministry of Education Grant-in-Aid for Scientific Research on Priority Areas in Japan. The JROB-1 features: 1) self-contained, 2) RT-Linux running on PG/AT processes vision and sensor processing, motion planning and control, 3) connected to a network via radio Ethernet as to utilize networked resources, 4) Fujitsu color tracking vision board and Hitachi general purpose vision processing board, 5) all parts are commercially available, and 6) it is extensible with respect to sensor, sensor processing hardware and software. JROB-1 is expected to be a common testbed for experiment and intelligent robotics research by integrating perception and motion.

The Spacebridge to Russia Project: internet-based telemedicine.

Abstract: The National Aeronautics and Space Administration (NASA) has been a pioneer in telemedicine since the beginning of the human spaceflight program in the early 1960s With the rapid evolution in computer technology and equally rapid development of computer networks, NASA and the Department of Surgery in Yale University's School of Medicine created a telemedicine testbed with the Russia Space Agency, the Spacebridge to Russia Project, using multimedia computers connected via the Internet Clinical consultations were evaluated in a store-and-forward mode using a variety of electronic media, packaged as digital files, and transmitted using Internet and World Wide Web tools These systems allow real-time Internet video teleconferencing between remotely located users over computer systems This report describes the project and the evaluation methods utilized for monitoring effectiveness of the communications The Spacebridge to Russia Project is a testbed for Internet-based telemedicine The Internet and current computer technologies (hardware and software) make telemedicine readily accessible and affordable for most health care providers Internet-based telemedicine is a communication tool that should become integral to global health care