Michael Daw

High-performance reliable multicasting for grid applications

Grid computing can be characterized as a distributed infrastructure that joins computing resources of multiple organizations together and enables the effective collaboration among researchers and engineers. Some of the future types of grid applications place very high demands on the network, often requiring the speedy delivery of the same data to multiple destinations. The communication in such cases is only feasible if reliable multicast is used. This paper addresses the use of reliable multicast in grid computing, identifying potential applications and requirements, and discusses how these requirements are met by protocols being standardized by the Internet Engineering Task Force (IETF). The emphasis of our study is on high-performance computing and communication, and on NORM protocols. The two existing implementations are compared with each other and with standard off-the-shelf TCP. Our findings are valid for applications that require high-speed reliable dissemination of large amounts of data over the Internet, such as RealityGrid, but can benefit other grid projects too. Unlike previous work, this paper considers the use of reliable multicast in one-to-few grid scenarios, and provides a practical comparison in the actual network environment to assess the suitability of such protocols.

Reliable multicast for the Grid: a case study in experimental computer science

In its simplest form, multicast communication is the process of sending data packets from a source to multiple destinations in the same logical multicast group. IP multicast allows the efficient transport of data through wide-area networks, and its potentially great value for the Grid has been highlighted recently by a number of research groups. In this paper, we focus on the use of IP multicast in Grid applications, which require high-throughput reliable multicast. These include Grid-enabled computational steering and collaborative visualization applications, and wide-area distributed computing. We describe the results of our extensive evaluation studies of state-of-the-art reliable-multicast protocols, which were performed on the UKs high-speed academic networks. Based on these studies, we examine the ability of current reliable multicast technology to meet the Grids requirements and discuss future directions.

Secure Access to Grid Information Service Using Shibboleth and PERMIS

Grid information service (GIS) is a core functional component of a grid that provides information about various resources and their status. Security underpins a GIS making secure access to a GIS an important issue. On the basis of our existing work on a GIS architecture, we further propose a security framework which leverages Shibboleth as the authentication infrastructure and combines PERMIS authorization technology. As a result, this security framework integrates the advantages of both Shibboleth cross-domain identity federation and PERMIS policy driven role based access control, thus presenting a new security model for secure access to a GIS.

Memetic: Semantic Meeting Memory

This paper introduces the memetic toolkit for recording meetings held over Internet-based video conferencing technologies, and making these navigable in linear and nonlinear ways. We introduce the tools and technologies that form the toolkit and discuss the semantics of the information they capture