Research into display sharing techniques for distributed computing environments

The X-based Display Sharing solution for distributed computing environments is described. The Display Sharing prototype includes the base functionality for telecast and display copy requirements. Since the prototype implementation is modular and the system design provided flexibility for the Mission Control Center Upgrade (MCCU) operational consideration, the prototype implementation can be the baseline for a production Display Sharing implementation. To facilitate the process the following discussions are presented: Theory of operation; System of architecture; Using the prototype; Software description; Research tools; Prototype evaluation; and Outstanding issues. The prototype is based on the concept of a dedicated central host performing the majority of the Display Sharing processing, allowing minimal impact on each individual workstation. Each workstation participating in Display Sharing hosts programs to facilitate the user's access to Display Sharing as host machine

MAGNET: A Virtual Shared Tuplespace Resource Manager

Traditional operating systems limit flexibility, performance and utilization of hardware resources by forcing applications to use inappropriate high-level abstractions, uniform protection schemes and high-level static resource management. This forced use of inappropriate services results in poor application and operating system performance. A radical new approach to operating systems design and construction is needed to meet the requirements of modern applications. Within our Centre, we are designing BITS: the Component Based Operating System, to address these issues.To realize its full potential, BITS requires a radically new resource management strategy. The operating system design gives an environment for implementing extensions, but a resource manager module is responsible for making them available. It allows system services to be specialized, replaced or extended to better serve application-specific needs.In this paper we propose the MAGNET Resource Manager enabling a free-market negotiation of application requests and server resources. It provides an additional level of flexibility for application participation in resource management. MAGNET also provides a platform for an additional runtime level of extensibility: dynamic modification and replacement of its parts during execution

A file server for the DistriX prototype : a multitransputer UNIX system

Bibliography: pages 90-94.The DISTRIX operating system is a multiprocessor distributed operating system based on UNIX. It consists of a number of satellite processors connected to central servers. The system is derived from the MINIX operating system, compatible with UNIX Version 7. A remote procedure call interface is used in conjunction with a system wide, end-to-end communication protocol that connects satellite processors to the central servers. A cached file server provides access to all files and devices at the UNIX system call level. The design of the file server is discussed in depth and the performance evaluated. Additional information is given about the software and hardware used during the development of the project. The MINIX operating system has proved to be a good choice as the software base, but certain features have proved to be poorer. The Inmos transputer emerges as a processor with many useful features that eased the implementation