The second Pegasus II Workshop (Pegasus '99)

The Moller Centre, Churchill College, Cambridge, UK

25th November, 1999

Hosted By:

The Systems Research Group
Computer Laboratory
University of Cambridge


Pegasus II takes the results of the Pegasus project as a starting point on which to build a complete distributed multimedia platform, including toolkits, user interfaces, filing systems and the emulation of familiar software environments. Most of this work is concentrated in the development of the Nemesis operating system.

Nemesis is an entirely new operating system, whose design is geared to the support of time-sensitive applications requiring a consistent Quality of Service (QoS), such as those which use multimedia. Nemesis provides fine-grained guaranteed levels of all system resources including CPU, memory, network bandwidth and disk bandwidth.

Pegasus '99 brings together researchers within the project and participants from other academic and industrial research institutions to present and discuss topics relating to resource management, single-address space operating systems, extensibility, secure partitioning, and quality of service.

Programme (Provisional)

Presentations are each 25 minutes long (approximately 20 minutes presentation followed by 5 minutes discussion). The emphasis is not on didactic presentation, but on discussion and interaction. The aim of the workshop is to stimulate debate and discussion in an informal setting.

9.30 Coffee & Welcome

Session 1: Future Directions

Introductory Remarks
Ian Leslie
University of Cambridge Computer Laboratory

System Challenges for Languages - Lessons Learned from Building Nemesis
Derek McAuley
Microsoft Research Cambirdge (LTD).

Securing Nemesis - Mimesis
Stephen Early
University of Cambridge Computer Laboratory

11.00 Coffee

Session 2: Open Platforms

An Extensible Virtual Machine
Timothy Harris
Citrix Systems (Cambridge) Ltd.

SwitchWare - Injecting Turing Machines into the Network
Jonathan Smith
University of Pennsylvania

XenoServers - Accountable Execution of Untrusted Code
Ian Pratt
University of Cambridge Computer Laboratory

12.30 Lunch

Session 3: Miscellany

Supporting Personalities in a SASOS
Rolf Neugebauer
Department of Computer Science, University of Glasgow

Lightweight Virtual Networks
Sean Rooney
IBM Research Zurich

Clockwise - A Hierarchical QoS-Aware Storage System
Peter Bosch
University of Twente

15.00 Coffee

Session 4: QoS and the Internet

Nemesis QoS versus Diffserv and Intserv
Bengt Ahlgren
Swedish Institute of Computer Science (SICS)

Scheduling TCP in the Nemesis Operating System
Thiemo Voigt
Swedish Institute of Computer Science (SICS)

Closing Remarks
Ian Leslie
University of Cambridge Computer Laboratory

17.00 Demonstrations (in the Atlas Room, Computer Laboratory)

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