18th IEEE Real-Time Systems Symposium: Work in Progress Sessions

Dear Colleagues: Following, the success of last year's Work In Progress (WIP) Sessions during RTSS'96, I am pleased to continue that tradition by presenting you 10 excellent WIP reports for RTSS'97. The prime purpose of RTSS WIP sessions is to provide researchers in Academia and Industry an opportunity to discuss their evolving ideas and gather feedback thereon from the real-time community at large. There were 16 submissions for WIP presentations, of which 10 have been accepted for presentation during the symposium and for inclusion in RTSS'97 WIP proceedings. If you would like to reference any article included in the RTSS'97 WIP Proceedings, please note that theses proceedings are published as a Technical Report from Boston University, Computer Science Department (BUCS-TR-97- 021). Many people worked hard to make the idea of holding the WIP sessions a reality. In particular, I would like to thank Kwei-Jay Lin for accommodating the WIP sessions within the busy schedule of RTSS'97. Also, I would like to thank all members of the RTSS'97 Program Committee who helped me review these submissions. Finally, I would like to thank all those who submitted their work to RTSS'97 WIP Sessions. I hope these sessions will prove beneficial, both to the WIP presenters and to RTSS'97 attendees. Azer Bestavros RTSS'97 WIP Chair December 1997.IEEE-CS TC-RT

Characterizing Group Communication Middleware for Real-time Distributed Systems

This paper presents our current work in characterizing the behavior of a real-time dependable distributed system, which must exhibit predictable behavior under load and in the presence of partial failures. We focus on measuring the end-to-end properties of the middleware implementing the real-time process group service, specifically its membership and message latency. The paper also describes the tools and techniques we have developed, along with some of the practical issues that arise in instrumenting a real-time distributed system. 1 Introduction A major focus of research at The Open Group Research Institute is the development of real-time dependable distributed systems. One of our goals is to provide our academic and industrial partners with configurable, reusable frameworks for research and further development. Target applications include factory automation, sensor monitoring and combat systems, which require predictable behavior, even in emergency conditions. Under this program,..

Edge device multi-unicasting for video streaming

©2003 IEEE. After a decade of research and development, IP multicast has still not been deployed widely in the global Internet due to many open technical issues: lack of admission control, poorly scaled with large number of groups, and requiring substantial infrastructure modifications. To provide the benefits of IP multicast without requiring direct router support or the presence of a physical broadcast medium, various Application Level Multicast (ALM) models have been attempted. However, there are still several problems with ALM: unnecessary coupling between an application and its multicasting supports, bottleneck problem at network access links and considerable processing power required at the end nodes to support ALM mechanisms. This paper proposes an architecture to address these problems by delegating application-multicasting support mechanisms to smart edge devices associated with the application end nodes. The architecture gives rise to an interesting Edge Device Any-casting technology that lies between the IP-multicasting and the Application Layer Multicasting and enjoys the benefits of both. Furthermore, the architecture may provide sufficient cost-benefit for adoption by service providers. The paper presents initial results obtained from the implementation of a video streaming application over the testbed that implements the proposed architecture

Using RDF to describe networks

Conventions such as iGrid 2005 and SuperComputing show that there is increasing demand for more service options on networks. For such networks, large teams of experts are needed to configure and manage them. In order to make the full potential of hybrid networks available to the ordinary user, the complexity must be reduced. This paper presents the idea of the Network Description Language (NDL), which builds on Semantic Web techniques to create a distributed Topology Knowledge Base (TKB). The TKB can provide a collection of reachability graphs, showing connectivity rules among physical and/or virtual entities. Latching onto the Semantic Web provides network management with a new breed of tools—bots, compilers, browsers, both commercial offthe-shelf (COTS) and open source. The approach appears to be applicable to the Global Lambda Integrated Facility (GLIF) as well as otherexperimental communities