|
| EPSRC Reference: |
GR/H77194/01 |
| Title: |
A QUALITY SERVICE ARCHITECTURE (QOS-A) FOR
MULTIMEDIA COMMUNICATIONS SYSTEMS |
| 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: |
|
|