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Details of Grant
EPSRC Reference: GR/H77194/01
Principal Investigator: Professor D Hutchison
Other Investigators:   Dr A Scott
Professor D Shepherd

Recognised Researchers:
Project Partner: Pre Nexus Migration

Department: Computing
Organisation: Lancaster University
Abstract: To define an OSI compatible Quality of Service Architecture (QoS-A). To develop the QoS-A in an ODP based distributed multimedia environment. To demonstrate the QoS-A implementation in a target application. To introduce the research results into the ISO QoS new work item. Progress: Following the definition of a base architecture supporting different QoS commitment classes (as detailed in last years report), the project has been concentrating on two main areas: the integration of compression standards into the architecture and network support for QoS. In the first area, the work is focused on the exploitation of compression standards to minimise both bandwidth and storage requirements and the use of filtering mechanisms which scale compressed media flows before they reach the end-system. In the second area, congestion control and resource allocation mechanisms have been designed for the local ATM environment. An extensive survey of ATM congestion control methods has also been completed. Currently, a call admission control method for local ATM is being developed and tested via simulation. The project has also been involved in a case study of how the QoS-A can accommodate an networked environment of low cost end-systems connected via local ATM. This work has led to an implementation plan for the support of low-cost multimedia end-systems in student laboratories at Lancaster. In the design, a hub switched ethernet acts as a concentrator for a number of workstations attached to an ATM link and each station has its own ethernet segment to avoid contention and unpredictability. The QoS-A based communications infrastructure for this environment will include signalling and resource allocation functions (including the use of filters) and a continuous media transport protocol accessible via a QoS extension of the Berkeley sockets interface in the UNIX environment. Finally, the project has been engaged in a fruitful collaboration with the SUMO project at Lancaster which is looking at QoS support in a microkernel operating system environment. The QoS-A resource allocation and scheduling functions have been imported into the SUMO environment which is leading to the development of a system in which hard guarantees of QoS can be made from source application process to sink application process including application level processing. This work is reported in a paper that appeared in a 1994 edition of IEEE Journal on Selected Areas in Communications on local ATM. The SUMO design is also intended as an integral component in an ODP based multimedia support infrastructure and thus directly addresses the ODP support objective of the QoS-A project The results of the project in general have been reported in a number of publications including INFOCOM '93, HPCS '93, NOSSDAV '93, HPN'94, IWACA '94, Chapter 11 of Networks and Distributed Systems Management (ed. M. Sloman, 1994), ACM Computer Communications Review, NOSSDAV '95, IEEE Journal on Selected Areas in Communications, Computer Networks and ISDN Systems, the 12th UK Teletraffic Symposium and the 2nd IFIP Workshop on Performance Modelling and Evaluation of ATM Networks. The results so far have also been introduced into the ISO QoS Framework standardisation activity in which our team is actively participating.
Starts: 01 November 1992 Ends: 30 April 1996 Value (£): 215,065
Scheme: Standard Research
EPSRC Research Topic Classifications:
  ICT Networks and Distributed Systems
EPSRC Industrial Sector Classifications: