Verifying distributed real-time properties of embedded systems via graph transformations and model checking

Component middleware provides dependable and efficient platforms that support key functional, and quality of service (QoS) needs of distributed real-time embedded (DRE) systems. Component middleware, however, also introduces challenges for DRE system developers, such as evaluating the predictability of DRE system behavior, and choosing the right design alternatives before committing to a specific platform or platform configuration. Model-based technologies help address these issues by enabling design-time analysis, and providing the means to automate the development, deployment, configuration, and integration of component-based DRE systems. To this end, this paper applies model checking techniques to DRE design models using model transformations to verify key QoS properties of component-based DRE systems developed using Real-time CORBA. We introduce a formal semantic domain for a general class of DRE systems that enables the verification of distributed non-preemptive real-time scheduling. Our results show that model-based techniques enable design-time analysis of timed properties and can be applied to effectively predict, simulate, and verify the event-driven behavior of component-based DRE systems. This research was supported by the NSF Grants CCR-0225610 and ACI-0204028 Gabor Madl is a Ph.D. student and a graduate student researcher at the Center for Embedded Computer Systems at the University of California, Irvine. His advisor is Nikil Dutt. His research interests include the formal verification, optimization, component-based composition, and QoS management of distributed real-time embedded systems. He received his M.S. in computer science from Vanderbilt University and in computer engineering from the Budapest University of Technology and Economics. Dr. Sherif Abdelwahed received his Ph.D. degree in Electrical and Computer Engineering from the University of Toronto, Canada, in 2001. During 2000–2001, he was a research scientist with the system diagnosis group at the Rockwell Scientific Company. Since 2001 he has been with the Department of Electrical Engineering and Computer Science at Vanderbilt University as a Research Assistant Professor. His research interests include verification and control of distributed real-time systems, and model-based diagnosis of discrete-event and hybrid systems. Dr. Douglas C. Schmidt is a Professor of Computer Science, Associate Chair of the Computer Science and Engineering program, and a Senior Researcher in the Institute for Software Integrated Systems (ISIS) all at Vanderbilt University. He has published over 300 technical papers and 6 books that cover a range of research topics, including patterns, optimization techniques, and empirical analyses of software frameworks and domain-specific modeling environments that facilitate the development of distributed real-time and embedded (DRE) middleware and applications. Dr. Schmidt has served as a Deputy Office Director and a Program Manager at DARPA, where he lead the national R&D effort on middleware for DRE systems. In addition to his academic research and government service, Dr. Schmidt has over fifteen years of experience leading the development of ACE, TAO, CIAO, and CoSMIC, which are widely used, open-source DRE middleware frameworks and model-driven tools that contain a rich set of components and domain-specific languages that implement patterns and product-line architectures for high-performance DRE systems.     

Integrated Adaptive QoS Management in Middleware: A Case Study

Distributed real-time and embedded (DRE) systems in which application requirements and environmental conditions may not be known a priori—or which may vary at run-time—can benefit from an adaptive approach to management of quality-of-service (QoS) to meet key constraints, such as end-to-end timeliness. Moreover, coordinated management of multiple QoS capabilities across multiple layers of applications and their supporting middleware can help to achieve necessary assurances of meeting these constraints.This paper offers two contributions to the study of adaptive DRE computing systems: (1) a case study of our integration of multiple middleware QoS management technologies to manage quality and timeliness of imagery adaptively within a representative DRE avionics system and (2) empirical results and analysis of the impact of that integration on key trade-offs between timeliness and image quality in that system.This work was supported in part by AFRL contract F33615-97-D-1155/0005 (WSOA), NSF ITR CCR-0312859, Siemens, and DARPA/AFRL contracts F33615-03-C-4112, F30602-98-C-0187 and F33615-00-C-1694. Approved for public release, distribution unlimited.Christopher D. Gill is an Assistant Professor in the Department of Computer Science and Engineering at Washington University in St. Louis. He has published over 50 refereed technical articles in leading journals, conferences, workshops, and book series. His research focuses on distributed real-time embedded systems, with particular emphasis on adaptive mresource management, scheduling, and software design and implementation for time-and-space constrained systems. Dr. Gill has chaired numerous workshop and conference program committees, and has participated widely in review panels and standards organizations in the distributed and real-time systems areas. The research he has led has produced several freely available open-source software frameworks including the Kokyu scheduling and dispatching framework and the nORB small-footprint real-time object request broker.Jeanna Gossett joined The Boeing Company in 1999 as a member of Bold Stroke/Open Systems Architecture team. Jeanna has worked on several CRAD projects including Weapon Systems Open Architecture (WSOA) where she was responsible for incorporating quality of service and resource management software technology into the fighter aircraft real-time embedded system application. Jeanna has since joined the F/A-18 New Product Development Mission Systems team. Prior to joining The Boeing Company in 1999, she worked in the telecommunications industry as an embedded systems developer at Ericsson and Siemens AG. Jeanna received a B.S. in Electrical Engineering from Southern Illinois University, Edwardsville and is a 2005 M.B.A. candidate at Washington University in St. Louis.David Corman is a Technical Fellow at the Boeing Company, located in St. Louis, Mo. Dave is the chief scientist for the Network Centric Operations (NCO) thrust in Phantom Works (PW) and is responsible for developing the NCO technology research agenda and investment strategy. He is also the Principle Investigator (PI) for a variety of Air Force and Defense Advanced Research Project Agency (DARPA) programs that are producing technologies for integrating legacy platforms into the emerging Global Information Grid and for autonomous control of unmanned systems. Since joining the former McDonnell-Douglas (now part of the Boeing Company) in 1983, Dave has worked on numerous projects ranging from embedded systems to large C4I and weapon systems. A major focus of Daves career has been on the development of C4I system simulations and in mission planning system development for aircraft and missiles. He has also served as a consultant to many weapon system and C4I programs in St. Louis, Seattle, and California. Prior to joining McDonnell-Douglas, Dave spent five years at the Johns Hopkins University Applied Physics Laboratory. He was the first recipient of a Naval Research Laboratory Fellowship from the University of Maryland—College Park where he received his PhD in Electrical Engineering in 1983.Joseph Loyall is a division scientist at BBN Technologies, where he leads the Distributed Real-time Embedded (DRE) systems research thrust in the Distributed Systems Advanced Middleware Technology group. He is actively involved in developing integrated dynamic resource management capabilities and advanced software engineering using model driven architecture (MDA) approaches, and in applying adaptive behavior to operational embedded systems such as collections of unmanned and manned air vehicles. Dr. Loyall has a Ph.D. and M.S. in computer science from the University of Illinois and a B.S. in computer science from Indiana University. He can be contacted at jloyall@bbn.com.Richard E. Schantz is a principal scientist at BBN Technologies in Cambridge, Mass., where he has been a key contributor to advanced distributed computing R&D for the past 30 years. His research has been instrumental in defining and evolving the concepts underlying middleware since its emergence in the early days of the Internet. He was directly responsible for developing the first operational distributed object computing capability and transitioning it to production use. More recently, he has led research efforts toward developing and demonstrating the effectiveness of middleware support for adaptively managed Quality Of Service control, as principal investigator on a number of key DARPA projects in the areas of adaptive real-time behavior, survivability and advanced software engineering. Schantz received his Ph.D. degree in Computer Science from the State University of New York at Stony Brook, in 1974.Michael Atighetchi is a senior scientist at BBN Technologies and a senior member of the Distributed Systems Advanced Middleware Technology group. His interests include use of adaptation in survivable systems, network and operating system security, and distributed coordination. Contact him at matighet@bbn. comDouglas C. Schmidt (d.schmidt@vanderbilt.edu) is a Professor of Electrical Engineering and Computer Science, Associate Chair of the Computer Science and Engineering program, and a Senior Researcher in the Institute for Software Integrated Systems (ISIS) at Vanderbilt University. He has published over 300 technical papers and books that cover a range of research topics, including patterns, optimization techniques, and empirical analyses of software frameworks and domain-specific modeling environments that facilitate the development of distributed real-time and embedded (DRE) middleware and applications running over high-speed networks and embedded system interconnects. Dr. Schmidt has served as a Deputy Office Director and a Program Manager at DARPA, where he led the national R&D effort on middleware for DRE systems.     

一种分布式实时嵌入式软件的构件模型Z-CCM

把运用于商务应用和桌面系统的中间件和构件化开发思想应用于分布式实时嵌入式(DistributedReal-timeandEmbedded,DRE)软件领域是当前的一个热门研究话题。CORBA构件模型(CORBAComponentModel,CCM)解决了跨平台语言无关的构件化开发问题,然而在提供QoS保证上CCM存在设计缺陷。论文首先分析了CCM的总体构架,接着提出了一种支持DRE软件开发的新的构件模型Z-CCM,这种构件模型从构件的实现框架、装配过程和运行时环境三方面对CCM进行了优化,以改进CCM在提供QoS保证上的缺陷,从而可以提高DRE软件的开发效率,文章最后介绍了Z-CCM的应用背景。     

Resource access control for dynamic priority distributed real-time systems

Many of today’s complex computer applications are being modeled and constructed using the principles inherent to real-time distributed object systems. In response to this demand, the Object Management Group’s (OMG) Real-Time Special Interest Group (RT SIG) has worked to extend the Common Object Request Broker Architecture (CORBA) standard to include real-time specifications. This group’s most recent efforts focus on the requirements of dynamic distributed real-time systems. One open problem in this area is resource access synchronization for tasks employing dynamic priority scheduling. This paper presents two resource synchronization protocols that meet the requirements of dynamic distributed real-time systems as specified by Dynamic Scheduling Real-Time CORBA 2.0 (DSRT CORBA). The proposed protocols can be applied to both Earliest Deadline First (EDF) and Least Laxity First (LLF) dynamic scheduling algorithms, allow distributed nested critical sections, and avoid unnecessary runtime overhead. These protocols are based on (i) distributed resource preclaiming that allocates resources in the message-based distributed system for deadlock prevention, (ii) distributed priority inheritance that bounds local and remote priority inversion, and (iii) distributed preemption ceilings that delimit the priority inversion time further. Chen Zhang is an Assistant Professor of Computer Information Systems at Bryant University. He received his M.S. and Ph.D. in Computer Science from the University of Alabama in 2000 and 2002, a B.S. from Tsinghua University, Beijing, China. Dr. Zhang’s primary research interests fall into the areas of distributed systems and telecommunications. He is a member of ACM, IEEE and DSI. David Cordes is a Professor of Computer Science at the University of Alabama; he has also served as Department Head since 1997. He received his Ph.D. in Computer Science from Louisiana State University in 1988, an M.S. in Computer Science from Purdue University in 1984, and a B.S. in Computer Science from the University of Arkansas in 1982. Dr. Cordes’s primary research interests fall into the areas of software engineering and systems. He is a member of ACM and a Senior Member of IEEE.     

组件模型(CCM)的多视点分析

中间件与组件相结合正成为分布式系统开发的一个主要方向。CORBA是一个主流的中间件,最新的CORBA3.0规范增加CORBA组件模型(CCM),完成了CORBA向“组件化”转化的目标。文章分析了CCM产生的原因和背景,并运用IEEEStd1471多视点的分析方法,较全面的从各个视点剖析了CORBA组件模型,并给出了CCM的一个完整的多视点视图和基于CORBA组件的软件开发过程。最后指出了CCM需要进一步研究和完善的地方。     

Preference update for e-commerce applications: Model,language, and processing

It is likely that customers issue requests based on out-of-date information in e-commerce application systems. Hence, the transaction failure rates would increase greatly. In this paper, we present a preference update model to address this problem. A preference update is an extended SQL update statement where a user can request the desired number of target data items by specifying multiple preferences. Moreover, the preference update allows easy extraction of criteria from a set of concurrent requests and, hence, optimal decisions for the data assignments can be made. We propose a group evaluation strategy for preference update processing in a multidatabase environment. The experimental results show that the group evaluation can effectively increase the customer satisfaction level with acceptable cost. Peng Li is the Chief Software Architect of didiom LLC. Before that, he was a visiting assistant professor of computer science department in Western Kentucky University. He received his Ph.D. degree of computer science from the University of Texas at Dallas. He also holds a B.Sc. and M.S. in Computer Science from the Renmin University of China. His research interests include database systems, database security, transaction processing, distributed and Internet computer and E-commerce. Manghui Tu received a Bachelor degree of Science from Wuhan University, P.R. China in 1996, and a Master Degree in Computer Science from the University of Texas at Dallas 2001. He is currently working toward the PhD degree in the Department of Computer Science at the University of Texas at Dallas. Mr. Tu’s research interests include distributed systems, grid computing, information security, mobile computing, and scientific computing. His PhD research work focus on the data management in secure and high performance data grid. He is a student member of the IEEE. I-Ling Yen received her BS degree from Tsing-Hua University, Taiwan, and her MS and PhD degrees in Computer Science from the University of Houston. She is currently an Associate Professor of Computer Science at the University of Texas at Dallas. Dr. Yen’s research interests include fault-tolerant computing, security systems and algorithms, distributed systems, Internet technologies, E-commerce, and self-stabilizing systems. She had published over 100 technical papers in these research areas and received many research awards from NSF, DOD, NASA, and several industry companies. She has served as Program Committee member for many conferences and Program Chair/Co-Chair for the IEEE Symposium on Application-Specific Software and System Engineering & Technology, IEEE High Assurance Systems Engineering Symposium, IEEE International Computer Software and Applications Conference, and IEEE International Symposium on Autonomous Decentralized Systems. She is a member of the IEEE. Zhonghang Xia received the B.S. degree in applied mathematics from Dalian University of Technology in 1990, the M.S. degree in Operations Research from Qufu Normal University in 1993, and the Ph.D. degree in computer science from the University of Texas at Dallas in 2004. He is now an assistant professor in the Department of Computer Science, Western Kentucky University, Bowling Green, KY. His research interests are in the area of multimedia computing and networking, distributed systems, and data mining.     

A multi-threshold online smoothing technique for variable rate multimedia streams

Variable bit rate (VBR) compression for media streams allocates more bits to complex scenes and fewer bits to simple scenes. This results in a higher and more uniform visual and aural quality. The disadvantage of the VBR technique is that it results in bursty network traffic and uneven resource utilization when streaming media. In this study we propose an online media transmission smoothing technique that requires no a priori knowledge of the actual bit rate. It utilizes multi-level buffer thresholds at the client side that trigger feedback information sent to the server. This technique can be applied to both live captured streams and stored streams without requiring any server side pre-processing. We have implemented this scheme in our continuous media server and verified its operation across real world LAN and WAN connections. The results show smoother transmission schedules than any other previously proposed online technique. This research has been funded in part by NSF grants EEC-9529152 (IMSC ERC), and IIS-0082826, DARPA and USAF under agreement nr. F30602-99-1-0524, and unrestricted cash/equipment gifts from NCR, IBM, Intel and SUN. Roger Zimmermann is currently a Research Assistant Professor with the Computer Science Department and a Research Area Director with the Integrated Media Systems Center (IMSC) at the University of Southern California. His research activities focus on streaming media architectures, peer-to-peer systems, immersive environments, and multimodal databases. He has made significant contributions in the areas of interactive and high quality video streaming, collaborative large-scale group communications, and mobile location-based services. Dr. Zimmermann has co-authored a book, a patent and more than seventy conference publications, journal articles and book chapters in the areas of multimedia and databases. He was the co-chair of the ACM NRBC 2004 workshop, the Open Source Software Competition of the ACM Multimedia 2004 conference, the short paper program systems track of ACM Multimedia 2005 and will be the proceedings chair of ACM Multimedia 2006. He is on the editorial board of SIGMOD DiSC, the ACM Computers in Entertainment magazine and the International Journal of Multimedia Tools and Applications. He has served on many conference program committees such as ACM Multimedia, SPIE MMCN and IEEE ICME. Cyrus Shahabi is currently an Associate Professor and the Director of the Information Laboratory (InfoLAB) at the Computer Science Department and also a Research Area Director at the NSF's Integrated Media Systems Center (IMSC) at the University of Southern California. He received his M.S. and Ph.D. degrees in Computer Science from the University of Southern California in May 1993 and August 1996, respectively. His B.S. degree is in Computer Engineering from Sharif University of Technology, Iran. He has two books and more than hundred articles, book chapters, and conference papers in the areas of databases and multimedia. Dr. Shahabi's current research interests include Peer-to-Peer Systems, Streaming Architectures, Geospatial Data Integration and Multidimensional Data Analysis. He is currently an associate editor of the IEEE Transactions on Parallel and Distributed Systems (TPDS) and on the editorial board of ACM Computers in Entertainment magazine. He is also the program committee chair of ICDE NetDB 2005 and ACM GIS 2005. He serves on many conference program committees such as IEEE ICDE 2006, ACM CIKM 2005, SSTD 2005 and ACM SIGMOD 2004. Dr. Shahabi is the recipient of the 2002 National Science Foundation CAREER Award and 2003 Presidential Early Career Awards for Scientists and Engineers (PECASE). In 2001, he also received an award from the Okawa Foundations. Kun Fu is currently a Ph.D candidate in computer science from the University of Southern California. He did research at the Data Communication Technology Research Institute and National Data Communication Engineering Center in China prior to coming to the United States and is currently working on large scale data stream recording architectures at the NSF's Integrated Media System Center (IMSC) and Data Management Research Laboratory (DMRL) at the Computer Science Department at USC. He received an MS in engineering science from the University of Toledo. He is a member of the IEEE. His research interests are in the area of scalable streaming architectures, distributed real-time systems, and multimedia computing and networking. Mehrdad Jahangiri was born in Tehran, Iran. He received the B.S. degree in Civil Engineering from University of Tehran at Tehran, in 1999. He is currently working towards the Ph.D. degree in Computer Science at the University of Southern California. He is currently a research assistant working on multidimensional data analysis at Integrated Media Systems Center (IMSC)—Information Laboratory (InfoLAB) at the Computer Science Department of the University of Southern California.     

Tradeoff and Sensitivity Analysis in Software Architecture Evaluation Using Analytic Hierarchy Process

Software architecture evaluation involves evaluating different architecture design alternatives against multiple quality-attributes. These attributes typically have intrinsic conflicts and must be considered simultaneously in order to reach a final design decision. AHP (Analytic Hierarchy Process), an important decision making technique, has been leveraged to resolve such conflicts. AHP can help provide an overall ranking of design alternatives. However it lacks the capability to explicitly identify the exact tradeoffs being made and the relative size of these tradeoffs. Moreover, the ranking produced can be sensitive such that the smallest change in intermediate priority weights can alter the final order of design alternatives. In this paper, we propose several in-depth analysis techniques applicable to AHP to identify critical tradeoffs and sensitive points in the decision process. We apply our method to an example of a real-world distributed architecture presented in the literature. The results are promising in that they make important decision consequences explicit in terms of key design tradeoffs and the architecture's capability to handle future quality attribute changes. These expose critical decisions which are otherwise too subtle to be detected in standard AHP results. Liming Zhu is a PHD candidate in the School of Computer Science and Engineering at University of New South Wales. He is also a member of the Empirical Software Engineering Group at National ICT Australia (NICTA). He obtained his BSc from Dalian University of Technology in China. After moving to Australia, he obtained his MSc in computer science from University of New South Wales. His principle research interests include software architecture evaluation and empirical software engineering. Aybüke Aurum is a senior lecturer at the School of Information Systems, Technology and Management, University of New South Wales. She received her BSc and MSc in geological engineering, and MEngSc and PhD in computer science. She also works as a visiting researcher in National ICT, Australia (NICTA). Dr. Aurum is one of the editors of “Managing Software Engineering Knowledge”, “Engineering and Managing Software Requirements” and “Value-Based Software Engineering” books. Her research interests include management of software development process, software inspection, requirements engineering, decision making and knowledge management in software development. She is on the editorial boards of Requirements Engineering Journal and Asian Academy Journal of Management. Ian Gorton is a Senior Researcher at National ICT Australia. Until Match 2004 he was Chief Architect in Information Sciences and Engineering at the US Department of Energy's Pacific Northwest National Laboratory. Previously he has worked at Microsoft and IBM, as well as in other research positions. His interests include software architectures, particularly those for large-scale, high-performance information systems that use commercial off-the-shelf (COTS) middleware technologies. He received a PhD in Computer Science from Sheffield Hallam University. Dr. Ross Jeffery is Professor of Software Engineering in the School of Computer Science and Engineering at UNSW and Program Leader in Empirical Software Engineering in National ICT Australia Ltd. (NICTA). His current research interests are in software engineering process and product modeling and improvement, electronic process guides and software knowledge management, software quality, software metrics, software technical and management reviews, and software resource modeling and estimation. His research has involved over fifty government and industry organizations over a period of 15 years and has been funded from industry, government and universities. He has co-authored four books and over one hundred and twenty research papers. He has served on the editorial board of the IEEE Transactions on Software Engineering, and the Wiley International Series in Information Systems and he is Associate Editor of the Journal of Empirical Software Engineering. He is a founding member of the International Software Engineering Research Network (ISERN). He was elected Fellow of the Australian Computer Society for his contribution to software engineering research.     

Context-aware trust negotiation in peer-to-peer service collaborations

Service-oriented architecture (SOA) and Software as a Service (SaaS) are the latest hot topics to software manufacturing and delivering, and attempt to provide a dynamic cross-organisational business integration solution. In a dynamic cross-organisational collaboration environment, services involved in a business process are generally provided by different organisations, and lack supports of common security mechanisms and centralized management middleware. On such occasions, services may have to achieve middleware functionalities and achieve business objectives in a pure peer-to-peer fashion. As the participating services involved in a business process may be selected and combined at run time, a participating service may have to collaborate with multiple participating services which it has no pre-existing knowledge in prior. This introduces some new challenges to traditional trust management mechanisms. Automated Trust Negotiation (ATN) is a practical approach which helps to generate mutual trust relationship for collaborating principals which may have no pre-existing knowledge about each other without in a peer-to-peer way. Because credentials often contain sensitive attributes, ATN defines an iterative and bilateral negotiation process for credentials exchange and specifies security policies that regulate the disclosure of sensitive credentials. Credentials disclosure in the iterative process may follow different orders and combinations, each of which forms a credential chain. It is practically desirable to identify the optimal credential chain that satisfies certain objectives such as minimum release of sensitive information and minimum performance penalty. In this paper we present a heuristic and context-aware algorithm for identifying the optimal chain that uses context-related knowledge to minimize 1) the release of sensitive information including both credentials and policies and 2) the cost of credentials retrieving. Moreover, our solution offers a hierarchical method for protecting sensitive policies and provides a risk-based strategy for handling credential circular dependency. We have implemented the ATN mechanisms based on our algorithm and incorporated them into the CROWN Grid middleware. Experimental results demonstrate their performance-related advantages over other existing solutions.

GigaE PM: a high performance communication facility using a Gigabit Ethernet

A high performance communication facility, called theGigaE PM, has been designed and implemented for parallel applications on clusters of computers using a Gigabit Ethernet. The GigaE PM provides not only a reliable high bandwidth and low latency communication, but also supports existing network protocols such as TCP/IP. A reliable communication mechanism for a parallel application is implemented on the firmware on a NIC while existing network protocols are handled by an operating system kernel. A prototype system has been implemented using an Essential Communications Gigabit Ethernet card. The performance results show that a 58.3 μs round trip time for a four byte user message, and 56.7 MBytes/sec bandwidth for a 1,468 byte message have been achieved on Intel Pentium II 400 MHz PCs. We have implemented MPICH-PM on top of the GigaE PM, and evaluated the NAS parallel benchmark performance. The results show that the IS class S performance on the GigaE PM is 1.8 times faster than that on TCP/IP. Shinji Sumimoto: He is a Senior Researcher of Parallel and Distributed System Software Laboratory at Real World Computing Partnership, JAPAN. He received BS degree in electrical engineering from Doshisha University. His research interest include parallel and distributed systems, real-time systems, and high performance communication facilities. He is a member of Information Processing Society of Japan. Hiroshi Tezuka: He is a Senior Researcher of Parallel and Distributed System Software Laboratory at Real World Computing Partnership, JAPAN. His research interests include real-time systems and operating system kernel. He is a member of the Information Processing Society of Japan, and Japan Society for Software Science and Technology. Atsushi Hori, Ph.D.: He is a Senior Researcher of Parallel and Distributed System Software Laboratory at Real World Computing Partnership, JAPAN. His current research interests include parallel operating system. He received B.S. and M.S. degrees in Electrical Engineering from Waseda University, and received Ph.D. from the University of Tokyo. He worked as a researcher in Mitsubishi Research Institute from 1981 to 1992. Hiroshi Harada: He is a Senior Researcher of Parallel and Distributed System Software Laboratory at Real World Computing Partnership, JAPAN. His research interests include distributed/parallel systems and distributed shared memory. He received BS degree in physics from Science University of Tokyo. He is a member of ACM and Information Processing Society of Japan. Toshiyuki Takahashi: He is a Researcher at Real World Computing Partnership since 1998. He received his B.S. and M.S. from the Department of Information Sciences of Science University of Tokyo in 1993 and 1995. He was a student of the Information Science Department of the University of Tokyo from 1995 to 1998. His current interests are in meta-level architecture for programming languages and high-performance software technologies. He is a member of Information Processing Society of Japan. Yutaka Ishikawa, Ph.D.: He is the chief of Parallel and Distributed System Software Laboratory at Real World Computing Partnership, JAPAN. He is currently temporary retirement from Electrotechnical Laboratory, MITI. His research interests include distributed/parallel systems, object-oriented programming languages, and real-time systems. He received the B.S., M.S. and Ph.D degrees in electrical engineering from Keio University. He is a member of the IEEE Computer Society, ACM, Information Processing Society of Japan, and Japan Society for Software Science and Technology.     

Managing complexity: middleware explained

Traditionally, most definitions seeking to characterize middleware suggest that it is the software that facilitates remote database access and systems transactions. More recently, the term has come to be associated-somewhat limitingly-with distributed platforms such as the Open Software Foundation's Distributed Computing Environment (DCE) and the Object Management Group's Common Object Request Broker Architecture (CORBA). And some have loosely applied it to systems as diverse as workflow support environments and even to the Web itself. We believe the essential role of middleware is to manage the complexity and heterogeneity of distributed infrastructures and thereby provide a simpler programming environment for distributed-application developers. It is therefore most useful to define middleware as any software layer that is placed above the distributed system's infrastructure-the network OS and APIs-and below the application layer     

Approximation algorithm for periodic real-time tasks with workload-dependent running-time functions

This paper addresses the problem of resource allocation for distributed real-time periodic tasks, operating in environments that undergo unpredictable changes and that defy the specification of meaningful worst-case execution times. These tasks are supplied by input data originating from various environmental workload sources. Rather than using worst-case execution times (WCETs) to describe the CPU usage of the tasks, we assume here that execution profiles are given to describe the running time of the tasks in terms of the size of the input data of each workload source. The objective of resource allocation is to produce an initial allocation that is robust against fluctuations in the environmental parameters. We try to maximize the input size (workload) that can be handled by the system, and hence to delay possible (costly) reallocations as long as possible. We present an approximation algorithm based on first-fit and binary search that we call FFBS. As we show here, the first-fit algorithm produces solutions that are often close to optimal. In particular, we show analytically that FFBS is guaranteed to produce a solution that is at least 41% of optimal, asymptotically, under certain reasonable restrictions on the running times of tasks in the system. Moreover, we show that if at most 12% of the system utilization is consumed by input independent tasks (e.g., constant time tasks), then FFBS is guaranteed to produce a solution that is at least 33% of optimal, asymptotically. Moreover, we present simulations to compare FFBS approximation algorithm with a set of standard (local search) heuristics such as hill-climbing, simulated annealing, and random search. The results suggest that FFBS, in combination with other local improvement strategies, may be a reasonable approach for resource allocation in dynamic real-time systems. David Juedes is a tenured associate professor and assistant chair for computer science in the School of Electrical Engineering and Computer Science at Ohio University. Dr. Juedes received his Ph.D. in Computer Science from Iowa State University in 1994, and his main research interests are algorithm design and analysis, the theory of computation, algorithms for real-time systems, and bioinformatics. Dr. Juedes has published numerous conference and journal papers and has acted as a referee for IEEE Transactions on Computers, Algorithmica, SIAM Journal on Computing, Theoretical Computer Science, Information and Computation, Information Processing Letters, and other conferences and journals. Dazhang Gu is a software architect and researcher at Pegasus Technologies (NeuCo), Inc. He received his Ph.D. in Electrical Engineering and Computer Science from Ohio University in 2005. His main research interests are real-time systems, distributed systems, and resource optimization. He has published conference and journal papers on these subjects and has refereed for the Journal of Real-Time Systems, IEEE Transactions on Computers, and IEEE Transactions on Parallel and Distributed Systems among others. He also served as a session chair and publications chair for several conferences. Frank Drews is an Assistant Professor of Electical Engineering and Computer Science at Ohio Unversity. Dr. Drews received his Ph.D. in Computer Science from the Clausthal Unversity of Technolgy in Germany in 2002. His main research interests are resource management for operating systems and real-time systems, and bioinformatics. Dr. Drews has numerous publications in conferences and journals and has served as a reviewer for IEEE Transactions on Computers, the Journal of Systems and Software, and other conferences and Journals. He was Publication Chair for the OCCBIO’06 conference, Guest Editor of a Special Issue of the Journal of Systems and Software on “Dynamic Resource Management for Distributed Real-Time Systems”, organizer of special tracks at the IEEE IPDPS WPDRTS workshops in 2005 and 2006. Klaus Ecker received his Ph.D. in Theoretical Physics from the University of Graz, Austria, and his Dr. habil. in Computer Science from the University of Bonn. Since 1978 he is professor in the Department of Computer Science at the Clausthal University of Technology, Germany, and since 2005 he is visiting professor at the Ohio University. His research interests are parallel processing and theory of scheduling, especially in real time systems, and bioinformatics. Prof. Ecker published widely in the above mentioned areas in well reputed journals and proceedings of international conferences as well. He is also the author of two monographs on scheduling theory. Since 1981 he is organizing annually international workshops on parallel processing. He is associate editor of Real Time Systems, and member of the German Gesellschaft fuer Informatik (GI) and of the Association for Computing Machinery (ACM). Lonnie R. Welch received a Ph.D. in Computer and Information Science from the Ohio State University. Currently, he is the Stuckey Professor of Electrical Engineering and Computer Science at Ohio University. Dr. Welch performs research in the areas of real-time systems, distributed computing and bioinformatics. His research has been sponsored by the Defense Advanced Research Projects Agency, the Navy, NASA, the National Science Foundation and the Army. Dr. Welch has twenty years of research experience in the area of high performance computing. In his graduate work at Ohio State University, he developed a high performance 3-D graphics rendering algorithm, and he invented a parallel virtual machine for object-oriented software. For the past 15 years his research has focused on middleware and optimization algorithms for high performance computing. His research has produced three successive generations of adaptive resource management (RM) middleware for high performance real-time systems. The project has resulted in two patents and more than 150 publications. Professor Welch also collaborates on diabetes research with faculty at Edison Biotechnology Institute and on genomics research with faculty in the Department of Environmental and Plant Biology at Ohio University. Dr. Welch is a member of the editorial boards of IEEE Transactions on Computers, The Journal of Scalable Computing: Practice and Experience, and The International Journal of Computers and Applications. He is also the founder of the International Workshop on Parallel and Distributed Real-time Systems and of the Ohio Collaborative Conference on Bioinformatics. Silke Schomann graduated in 2003 with a M.Sc. in Computer Science from Clausthal University Of Technology, where she has been working as a scientific assistant since then. She is currently working on her Ph.D. thesis in computer science at the same university.     

A study of the model and algorithms for handling location-dependent continuous queries

Advances in wireless and mobile computing environments allow a mobile user to access a wide range of applications. For example, mobile users may want to retrieve data about unfamiliar places or local life styles related to their location. These queries are called location-dependent queries. Furthermore, a mobile user may be interested in getting the query results repeatedly, which is called location-dependent continuous querying. This continuous query emanating from a mobile user may retrieve information from a single-zone (single-ZQ) or from multiple neighbouring zones (multiple-ZQ). We consider the problem of handling location-dependent continuous queries with the main emphasis on reducing communication costs and making sure that the user gets correct current-query result. The key contributions of this paper include: (1) Proposing a hierarchical database framework (tree architecture and supporting continuous query algorithm) for handling location-dependent continuous queries. (2) Analysing the flexibility of this framework for handling queries related to single-ZQ or multiple-ZQ and propose intelligent selective placement of location-dependent databases. (3) Proposing an intelligent selective replication algorithm to facilitate time- and space-efficient processing of location-dependent continuous queries retrieving single-ZQ information. (4) Demonstrating, using simulation, the significance of our intelligent selective placement and selective replication model in terms of communication cost and storage constraints, considering various types of queries. Manish Gupta received his B.E. degree in Electrical Engineering from Govindram Sakseria Institute of Technology & Sciences, India, in 1997 and his M.S. degree in Computer Science from University of Texas at Dallas in 2002. He is currently working toward his Ph.D. degree in the Department of Computer Science at University of Texas at Dallas. His current research focuses on AI-based software synthesis and testing. His other research interests include mobile computing, aspect-oriented programming and model checking. Manghui Tu received a Bachelor degree of Science from Wuhan University, P.R. China, in 1996, and a Master's Degree in Computer Science from the University of Texas at Dallas 2001. He is currently working toward the Ph.D. degree in the Department of Computer Science at the University of Texas at Dallas. Mr. Tu's research interests include distributed systems, wireless communications, mobile computing, and reliability and performance analysis. His Ph.D. research work focuses on the dependent and secure data replication and placement issues in network-centric systems. Latifur R. Khan has been an Assistant Professor of Computer Science department at University of Texas at Dallas since September 2000. He received his Ph.D. and M.S. degrees in Computer Science from University of Southern California (USC) in August 2000 and December 1996, respectively. He obtained his B.Sc. degree in Computer Science and Engineering from Bangladesh University of Engineering and Technology, Dhaka, Bangladesh, in November of 1993. Professor Khan is currently supported by grants from the National Science Foundation (NSF), Texas Instruments, Alcatel, USA, and has been awarded the Sun Equipment Grant. Dr. Khan has more than 50 articles, book chapters and conference papers focusing in the areas of database systems, multimedia information management and data mining in bio-informatics and intrusion detection. Professor Khan has also served as a referee for database journals, conferences (e.g. IEEE TKDE, KAIS, ADL, VLDB) and he is currently serving as a program committee member for the 11th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (SIGKDD2005), ACM 14th Conference on Information and Knowledge Management (CIKM 2005), International Conference on Database and Expert Systems Applications DEXA 2005 and International Conference on Cooperative Information Systems (CoopIS 2005), and is program chair of ACM SIGKDD International Workshop on Multimedia Data Mining, 2004. Farokh Bastani received the B.Tech. degree in Electrical Engineering from the Indian Institute of Technology, Bombay, and the M.S. and Ph.D. degrees in Computer Science from the University of California, Berkeley. He is currently a Professor of Computer Science at the University of Texas at Dallas. Dr. Bastani's research interests include various aspects of the ultrahigh dependable systems, especially automated software synthesis and testing, embedded real-time process-control and telecommunications systems and high-assurance systems engineering. Dr. Bastani was the Editor-in-Chief of the IEEE Transactions on Knowledge and Data Engineering (IEEE-TKDE). He is currently an emeritus EIC of IEEE-TKDE and is on the editorial board of the International Journal of Artificial Intelligence Tools, the International Journal of Knowledge and Information Systems and the Springer-Verlag series on Knowledge and Information Management. He was the program cochair of the 1997 IEEE Symposium on Reliable Distributed Systems, 1998 IEEE International Symposium on Software Reliability Engineering, 1999 IEEE Knowledge and Data Engineering Workshop, 1999 International Symposium on Autonomous Decentralised Systems, and the program chair of the 1995 IEEE International Conference on Tools with Artificial Intelligence. He has been on the program and steering committees of several conferences and workshops and on the editorial boards of the IEEE Transactions on Software Engineering, IEEE Transactions on Knowledge and Data Engineering and the Oxford University Press High Integrity Systems Journal. I-Ling Yen received her B.S. degree from Tsing-Hua University, Taiwan, and her M.S. and Ph.D. degrees in Computer Science from the University of Houston. She is currently an Associate Professor of Computer Science at University of Texas at Dallas. Dr. Yen's research interests include fault-tolerant computing, security systems and algorithms, distributed systems, Internet technologies, E-commerce and self-stabilising systems. She has published over 100 technical papers in these research areas and received many research awards from NSF, DOD, NASA and several industry companies. She has served as Program Committee member for many conferences and Program Chair/Cochair for the IEEE Symposium on Application-Specific Software and System Engineering & Technology, IEEE High Assurance Systems Engineering Symposium, IEEE International Computer Software and Applications Conference, and IEEE International Symposium on Autonomous Decentralized Systems. She has also served as a guest editor for a theme issue of IEEE Computer devoted to high-assurance systems.     

An empirical study of predicting software faults with case-based reasoning

The resources allocated for software quality assurance and improvement have not increased with the ever-increasing need for better software quality. A targeted software quality inspection can detect faulty modules and reduce the number of faults occurring during operations. We present a software fault prediction modeling approach with case-based reasoning (CBR), a part of the computational intelligence field focusing on automated reasoning processes. A CBR system functions as a software fault prediction model by quantifying, for a module under development, the expected number of faults based on similar modules that were previously developed. Such a system is composed of a similarity function, the number of nearest neighbor cases used for fault prediction, and a solution algorithm. The selection of a particular similarity function and solution algorithm may affect the performance accuracy of a CBR-based software fault prediction system. This paper presents an empirical study investigating the effects of using three different similarity functions and two different solution algorithms on the prediction accuracy of our CBR system. The influence of varying the number of nearest neighbor cases on the performance accuracy is also explored. Moreover, the benefits of using metric-selection procedures for our CBR system is also evaluated. Case studies of a large legacy telecommunications system are used for our analysis. It is observed that the CBR system using the Mahalanobis distance similarity function and the inverse distance weighted solution algorithm yielded the best fault prediction. In addition, the CBR models have better performance than models based on multiple linear regression. Taghi M. Khoshgoftaar is a professor of the Department of Computer Science and Engineering, Florida Atlantic University and the Director of the Empirical Software Engineering Laboratory. His research interests are in software engineering, software metrics, software reliability and quality engineering, computational intelligence, computer performance evaluation, data mining, and statistical modeling. He has published more than 200 refereed papers in these areas. He has been a principal investigator and project leader in a number of projects with industry, government, and other research-sponsoring agencies. He is a member of the Association for Computing Machinery, the IEEE Computer Society, and IEEE Reliability Society. He served as the general chair of the 1999 International Symposium on Software Reliability Engineering (ISSRE’99), and the general chair of the 2001 International Conference on Engineering of Computer Based Systems. Also, he has served on technical program committees of various international conferences, symposia, and workshops. He has served as North American editor of the Software Quality Journal, and is on the editorial boards of the journals Empirical Software Engineering, Software Quality, and Fuzzy Systems. Naeem Seliya received the M.S. degree in Computer Science from Florida Atlantic University, Boca Raton, FL, USA, in 2001. He is currently a Ph.D. candidate in the Department of Computer Science and Engineering at Florida Atlantic University. His research interests include software engineering, computational intelligence, data mining, software measurement, software reliability and quality engineering, software architecture, computer data security, and network intrusion detection. He is a student member of the IEEE Computer Society and the Association for Computing Machinery.     

AgentTeamwork: Coordinating grid-computing jobs with mobile agents

AgentTeamwork is a grid-computing middleware system that dispatches a collection of mobile agents to coordinate a user job over remote computing nodes in a decentralized manner. Its utmost focus is to maintain high availability and dynamic balancing of distributed computing resources to a parallel-computing job. For this purpose, a mobile agent is assigned to each process engaged in the same job, monitors its execution at a different machine, takes its periodical execution snapshot, moves it to a lighter-loaded machine, and resumes it from the latest snapshot upon an accidental crash. The system also restores broken inter-process communication involved in the same job using its error-recoverable socket and mpiJava libraries in collaboration among mobile agents. We have implemented the first version of our middleware including a mobile agent execution platform, error-recoverable socket and mpiJava API libraries, a job wrapper program, and several types of mobile agents such as commander, resource, sentinel, and bookkeeper agents, each orchestrating, allocating resources to, monitoring and maintaining snapshots of a user process respectively. This paper presents AgentTeamwork’s execution model, its implementation techniques, and our performance evaluation using the Java Grande benchmark test programs. Munehiro Fukuda received a B.S. from the College of Information Sciences and an M.S. from the Master’s Program in Science and Enginnering at the University of Tsukuba in 1986 and 1988. He received his M.S. and Ph.D. in Information and Computer Science at the University of California at Irvine in 1995 and 1997, respectively. He worked at IBM Tokyo Research Laboratory from 1988 to 1993 and taught at the University of Tsukuba from 1998 to 2001. Since 2001, he has been an assistant professor at Computing & Software Systems, the University of Washington, Bothell. His research interests include mobile agents, multi-threading, cluster computing, grid computing and distributed simulations. Koichi Kashiwagi received a Bachelor of Science degree from the Faculty of Science, Ehime University in 2000 and a Master of Engineering degree from the Department of Compter Science, Ehime University in 2002. In 2004 he became a research assistant in Department of Compter Science, Ehime University. His research interests include distributed computing, job scheduling, and grid computing. Shin-ya Kobayashi received the B.E. degree, M.E. degree, and Dr.E. degree in Communication Engineering from Osaka University in 1985, 1988, and 1991 respectively. From 1991 to 1999, he was on the faculty of Engineering at Kanazawa University, Japan. From 1999 to 2004, He was an Associate Professor in the Department of Computer Science, Ehime University. He is a Professor at Graduate School of Science and Engineering, Ehime University. His research interests include distributed processing, and parallel processing. He is a member of the Information Processing Society of Japan, the Institute of Electrical Engineers of Japan, IEEE, and ACM.     

一种用于软件通信体系结构的构件模型

软件通信体系结构(SoftwareCommunicationsArchitecture,简称SCA)已被软件无线电(SoftwareDefinedRadio,简称SDR)论坛采纳为嵌入式系统的标准通信软件结构。SCA提供了一种支持通信软件和硬件可移植、可配置、可扩充和可重用的软件平台,但作为构件框架时仍显不足,主要是缺乏明确的构件模型。在研究CORBA构件模型(CORBAComponentModel,简称CCM)基础上,提出了适用于SCA的轻量级(Lightweight,简称Lw)CORBA构件模型———LwCCM。     

A purely reactive navigation scheme for dynamic environments using Case-Based Reasoning

This paper presents a new sonar based purely reactive navigation technique for mobile platforms. The method relies on Case-Based Reasoning to adapt itself to any robot and environment through learning, both by observation and self experience. Thus, unlike in other reactive techniques, kinematics or dynamics do not need to be explicitly taken into account. Also, learning from different sources allows combination of their advantages into a safe and smooth path to the goal. The method has been succesfully implemented on a Pioneer robot wielding 8 Polaroid sonar sensors. Cristina Urdiales is a Lecturer at the Department of Tecnología Electrónica (DTE) of the University of Málaga (UMA). She received a MSc degree in Telecommunication Engineering at the Universidad Politécnica de Madrid (UPM) and her Ph.D. degree at University of Málaga (UMA). Her research is focused on robotics and computer vision. E.J. Pérez was born in Barcelona, Spain, in 1974. He received his title of Telecommunication Engineering from the University of Málaga, Spain, in 1999. During 1999 he worked in a research project under a grant by the Spanish CYCIT. From 2000 to the present day he has worked as Assistant Professor in the Department of Tecnología Electrónica of the University of Málaga. His research is focused on robotics and artificial vision. Javier Vázquez-Salceda is an Associate Researcher of the Artificial Intelligence Section of the Software Department (LSI), at the Technical University of Catalonia (UPC). Javier obtained an MSc degree in Computer Science at UPC. After his master studies he became research assistant in the KEMLg Group at UPC. In 2003 he presented his Ph.D. dissertation (with honours), which has been awarded with the 2003 ECCAI Artificial Intelligence Dissertation Award. The dissertation has been also recently published as a book by Birkhauser-Verlag. From 2003 to 2005 he was researcher in the Intelligent Systems Group at Utrecht University. Currently he is again member of the KEMLg Group at UPC. His research is focused on theoretical and applied issues of Normative Systems, software and physical agents' autonomy and social control, especially in distributed applications for complex domains such as eCommerce or Medicine. Miquel Sànchez-Marrè (Barcelona, 1964) received a Ph.D. in Computer Science in 1996 from the Technical University of Catalonia (UPC). He is Associate Professor in the Computer Software Department (LSI) of the UPC since 1990 (tenure 1996). He was the head of the Artificial Intelligence section of LSI (1997–2000). He is a pioneer member of International Environmental Modelling and Software Society (IEMSS) and a board member of IEMSS also, since 2000. He is a member of the Editorial Board of International Journal of Applied Intelligence, since October 2001. Since October 2004 he is Associate Editor of Environmental Modelling and Software journal. His main research topics are case-based reasoning, machine learning, knowledge acquisition and data mining, knowledge engineering, intelligent decision-support systems, and integrated AI architectures. He has an special interest on the application of AI techniques to Environmental Decision Support Systems. Francisco Sandoval was born in Spain in 1947. He received the title of Telecommunication Engineering and Ph.D. degree from the Technical University of Madrid, Spain, in 1972 and 1980, respectively. From 1972 to 1989 he was engaged in teaching and research in the fields of opto-electronics and integrated circuits in the Universidad Politécnica de Madrid (UPM) as an Assistant Professor and a Lecturer successively. In 1990 he joined the University of Málaga as Full Professor in the Department of Tecnología Electrónica. He is currently involved in autonomous systems and foveal vision, application of Artificial Neural Networks to Energy Management Systems, and in Broad Band and Multimedia Communication.     

Global Control of Robotic Highway Safety Markers: A Real-time Solution

This paper presents the design and implementation of a real-time solution for the global control of robotic highway safety markers. Problems addressed in the system are: (1) poor scalability and predictability as the number of markers increases, (2) jerky movement of markers, and (3) misidentification of safety markers caused by objects in the environment.An extensive analysis of the system and two solutions are offered: a basic solution and an enhanced solution. They are built respectively upon two task models: the periodic task model and the variable rate execution (VRE) task model. The former is characterized by four static parameters: phase, period, worst case execution time and relative deadline. The latter has similar parameters, but the parameter values are allowed to change at arbitrary times.The use of real-time tasks and scheduling techniques solve the first two problems. The third problem is solved using a refined Hough transform algorithm and a horizon scanning window. The approach decreases the time complexity of traditional implementations of the Hough transform with only slightly increased storage requirements.Supported, in part, by grants from the National Science Foundation (CCR-0208619 and CNS-0409382) and the National Academy of Sciences Transportation Research Board-NCHRP IDEA Program (Project #90).Jiazheng Shi received the B.E. and M.E. degrees in electrical engineering from Beijing University of Posts and Telecommunications in 1997 and 2000, respectively. In 2000, he worked with the Global Software Group, Motorola Inc. Currently, he is a Ph.D. candidate in the Computer Science and Engineering Department at the University of Nebraska–Lincoln. His research interests are automated human face recognition, image processing, computer vision, approximate theory, and linear system optimization.Steve Goddard is a J.D. Edwards Associate Professor in the Department of Computer Science & Engineering at the University of Nebraska–Lincoln. He received the B.A. degree in computer science and mathematics from the University of Minnesota (1985). He received the M.S. and Ph.D. degrees in computer science from the University of North Carolina at Chapel Hill (1995, 1998).His research interests are embedded, real-time and distributed systems with emphases in high assurance systems engineering and real-time, rate-based scheduling theory.Anagh Lal received a B.S. degree in Computer Science from the University of Mumbai (Bombay), Mumbai, in 2001. He is currently a graduate research assistant at the University of Nebraska–Lincoln working on a M.S. in Computer Science, and a member of the ConSystLab. His research interests lie in Databases, Constraint Processing and Real Time Systems. Anagh will be graduating soon and is looking for positions at research institutions.Jason Dumpert received a B.S. degree in electrical engineering from the University of Nebraska–Lincoln in 2001. He received a M.S. degree in electrical engineering from the University of Nebraska-Lincoln in 2004. He is currently a graduate research assistant at the University of Nebraska-Lincoln working on a Ph.D. in biomedical engineering. His research interests include mobile robotics and surgical robotics.Shane M. Farritor is an Associate Professor in the University of Nebraska–Lincolns Department of Mechanical Engineering. His research interests include space robotics, surgical robotics, biomedical sensors, and robotics for highway safety. He holds courtesy appointments in both the Department of Surgery and the Department of Orthopaedic Surgery at the University of Nebraska Medical Center, Omaha. He serves of both the AIAA Space Robotics and Automation technical committee and ASME Dynamic Systems and Control Robotics Panel. He received M.S. and Ph.D. degrees from M.I.T.     

RHiNET-2/SW: a high-throughput, compact network-switch using 8.8-gbit/s optical interconnection

We have developed a high-throughput, compact network switch (the RHiNET-2/SW) for a distributed parallel computing system. Eight pairs of 800-Mbit/s×12-channel optical interconnection modules and a CMOS ASIC switch are integrated on a compact circuit board. To realize high-throughput (64 Gbit/s) and low-latency network, the SW-LSI has a customized high-speed LVDS I/O interface, and a high-speed internal SRAM memory in a 784-pin BGA one-chip package. We have also developed device implementation technologies to overcome the electrical problems (loss and crosstalk) caused by such high integration. The RHiNET-2/SW system enables high-performance parallel processing in a distributed computing environment. Shinji Nishimura: He is a researcher in the Department of Network System at the Central Research Laboratory, Hitachi Ltd., at Tokyo. He obtained his bachelors degree in Electronics Engineering from the University of Tokyo in 1989, and his M.E. from the University of Tokyo in 1991. He joined a member of the Optical Interconnection Hitachi Laboratory from 1992. His research interests are in hardware technology for the optical interconnection technologies in the computer and communication systems. Katsuyoshi Harasawa: He is a Senior Enginner of Hitachi Communication Systems Inc. He obtained his bachelors degree in Electrical Engineering from Tokyo Denki University. He is a chief of development of the devices and systems for the optical telecommunication. He was engaged in Development of Optical Reciever and Transmitter module. He joined RWCP project from 1997. His research interests are in hardward technology for optical interconnection in distributed parallel computing system (RHiNET). Nobuhiro Matsudaira: He is a engineer in the Hitachi Communication Systems, Inc. He obtained his bachelors degree in Mercantile Marine Engineering from the Kobe University of Mercantile Marine in 1986. He was engaged in Development of Optical Reciever and Transmitter module at 2.4 Gbit/s to 10Gbit/s. He joined RWCP project from 1998. His reserch interests are in hardware technology for the optical interconnection technology in the computer and communication systems. Shigeto Akutsu: He is a staff in Hitachi Communication Systems Inc. He obtained his bachelors degree in Electronics from Kanagawa University, Japan in 1998. His research interests are hardware technology for the optical interconnection technology in the computer and communication systems. Tomohiro Kudoh, Ph.D.: He received Ph.D. degree from Keio University, Japan in 1992. He has been chief of the parallel and distributed architecture laboratory, Real World Computing Partnership since 1997. His research interests include the area of parallel processing and network for high performance computing. Hiroaki Nishi: He received B.E., M.E. from Keio University, Japan, in 1994, 1996, respectively. He joined Parallel & Distributed Architecture Laboratory, Real World Computing Partnership in 1999. He is currently working on his Ph.D. His research interests include area of interconnection networks. Hideharu Amano, Ph.D.: He received Ph.D. degree from Keio University, Japan in 1986. He is now an Associate Professor in the Department of Information and Computer Science, Keio University. His research interests include the area of parallel processing and reconfigurable computing.