About Us
We are conducting research into quantitative and qualitative modelling and analysis techniques for large scale systems, motivated by applications in:
- energy-aware computing
- smart environments
- security protocols
- mobile ad hoc networks
- resource management
We work with Markov chains, process algebra, stochastic reward nets, queueing theory and simulation.
The aim is to produce a set of techniques capable of handling the complexity and scale of modern applications and to apply these techniques in interesting developing domains.
People
- Choman Abdullah, PhD student
- Xiao Chen, former PhD student
- Matt Forshaw, Teaching Fellow
- Katya Gilly, former visiting researcher
- Michael Harrison, Emeritus Professor
- Said Kamil, PhD student
- Kyungsup Kim, former visiting researcher
- Simon Martin, former PhD student
- Michele Mazzucco, former PhD student
- Isi Mitrani, Emeritus Professor
- Jennie Palmer, Former Lecturer
- Joris Slegers, former PhD student
- Nigel Thomas, Reader
- Osama Younes, Former PhD student
- Yishi Zhao, Former PhD student
Projects
- CAMPA: Compositional Analysis in Markovian Process Algebra
EPSRC EP/G050724/1 Sept 2009-Mar 2010.
This was a six month collaboration between Nigel Thomas and Prof Peter Harrison (the PI) at Imperial College London. The aim of the project was to extend Harrison's Reversed Compound Agent Theorem to include models which have an approximate product form solution or a non-product form decomposition.
- AMPS: Analysis of Massively Parallel stochastic systems
EPSRC EP/G011389/1 Mar 2009-Jan 2013.
This was a joint project between Newcastle University and Imperial College London (Drs Bradley and Knottenbelt) also involving IBM (UK) and the University of Illinois (Urbana-Champagne). The aim of the project is to develop analysis techniques for systems with very large numbers of replicated components that arise in many disciplines. The project is considering various case studies in the area of security (trust) and smart environments.
- DOPCHE: Dynamic Operating Policies for Commercial Hosting Environments
EPSRC EP/C009797/1 Oct 2005-Jan 2009.
This was a joint project between the Universities of Newcastle and Warwick also involving BT, HP and IBM. The PI at Newcastle was Prof Isi Mitrani. The aim of the project was to develop policies for hosting Grid based applications to provide high service quality and efficient resource management.
Recent Publications
Energy-aware computing
- I. Mitrani, Managing performance and power consumption in a server farm. Annals OR 202(1):121-134, 2013.
- M. Forshaw and N. Thomas, A novel approach to energy efficient content distribution with BitTorrent, in: Computer Performance Engineering: EPEW/UKPEW 2012, LNCS 7587, Springer, 2012.
- I. Mitrani, Trading Power Consumption against Performance by Reserving Blocks of Servers. in: Computer Performance Engineering: EPEW/UKPEW 2012, LNCS 7587, Springer, 2012.
- F. Xia, A. Mokhov, Y. Zhou, Y. Chen, I. Mitrani, D. Shang, D. Sokolov, A. Yakovlev, Towards power-elastic systems through concurrency management, Computers & Digital Techniques, 6(1):33-42, 2012.
- M. Mazzucco and I. Mitrani, Empirical evaluation of power saving policies for data centers. SIGMETRICS Performance Evaluation Review, 40(3):18-22, 2012.
- I. Mitrani, Service center trade-offs between customer impatience and power consumption. Performance Evalaluation 68(11), 1222-1231, 2011.
- I. Mitrani, Management of Server Farms for Performance and Profit, Computer Journal, 53, 7, 1038-1044, 2010.
- Y. Chen, I. Mitrani, D. Shang, F. Xia, A. Yakovlev, Stochastic Analysis of Power, Latency and the Degree of Concurrency. In: IEEE International Symposium on Circuits and Systems, Paris, 2010.
- I. Mitrani, Managing Performance and Power Consumption in a Server Farm, 3rd Madrid Conference on Queueing Theory, Toledo, 2010.
- J. Slegers, N. Thomas and I. Mitrani, Dynamic server allocation for power and performance, in: Performance Evaluation - Metrics, Models and Benchmarks: SPEC Int'l Performance Evaluation Workshop, LNCS 5119, Springer Verlag, 2008.
- N. Thomas, A PEPA model of a threshold policy sleeping server, in: Proc. 24th UK Performance Engineering Workshop, Imperial College London, 2008.
Smart environments
- X. Chen, M. Harrison and N. Thomas, Performance evaluation of dynamic scheduling within a smart hospital environment, in: Proc. 1st Int'l Workshop on Healthcare Systems Engineering, IEEE Computer Society, 2011.
- M. Massink, A. Bracciali, D. Latella, M. Harrison, (2010) A Scalable Fluid Flow Process Algebraic Approach to Emergency Egress Analysis. In Proceedings of the 8th IEEE International Conference on Software Engineering And Formal Methods (SEFM2010). pp. 169-180. IEEE, 2010.
- M. Massink, D. Latella, A. Bracciali, M. Harrison, (2010) A Process Algebraic Fluid Flow Model of Emergency Egress. CNR-ISTI Technical report 2010-TR012, 2010.
- M. Massink, M. Harrison, D. Latella (2010) Scalable analysis of collective behaviour in smart service systems. Sung Y. Shin, Sascha Ossowski, Michael Schumacher, Mathew J. Palakal, Chih-Cheng Hung (Eds.): Proceedings of the 2010 ACM Symposium on Applied Computing (SAC), Sierre, Switzerland, March 22-26, 2010. ACM 2010, ISBN 978-1-60558-639-7 pp. 1173-1180
- M. Harrison and M. Massink, (2010) Modelling interactive experience, function and performance in ubiquitous systems, Electronic Notes in Theoretical Computer Science Vol. 261, pp 23-42 Elsevier B.V., 2010 ISSN 1571-0661
- X. Chen and N. Thomas, Performance Evaluation of Scheduling in a Smart Environment, in: Proc. 26th UK Performance Engineering Workshop, University of Warwick, 2010.
- M. Harrison, M. Massink and D. Latella, (2009) Engineering Crowd Interaction within Smart Environments, editors, G. Calvary, T.C.N. Graham and P. Gray, Proceedings of the ACM SIGCHI Symposium on Engineering Interactive Computing Systems, ACM Press, pp. 117-122.
- M. Massink, D. Latella, M.H. ter Beek, M. Harrison, and M. Loreti (2008) A Fluid Flow Approach to Usability Analysis of Multi-user Systems. In Engineering Interactive Systems 2008 - Proceedings of the 2nd Conference on Human-Centered Software Engineering (HCSE'08), Pisa, Italy (P. Forbrig and F. Paterno, eds.), Lecture Notes in Computer Science 5247, Springer-Verlag, Berlin, 166-180.
Security protocols
- N. Thomas and Y. Zhao, Performance modelling of security protocols, Performance and Security Modelling & Evaluation of Cooperative Heterogeneous Networks (HETNETS 2013), IFIP, 2013.
- Y. Zhao and N. Thomas, A simplified solution of a PEPA model of the Kerberos protocol, in: Proc. 1st Int'l Workshop on Service Oriented QoS Management from Theory to Practice, IEEE Computer Society, 2011.
- Y. Zhao and N. Thomas, Efficient solutions of a PEPA model of a key distribution centre, Performance Evaluation, 67(8), pp. 740-756, 2010.
- Y. Zhao and N. Thomas, Comparing Methods for the Efficient Analysis of PEPA Models of Non-repudiation Protocols, in: Proc. 15th Int'l Conference on Parallel and Distributed Systems, IEEE Computer Society, 2009.
- Y. Zhao and N. Thomas, Experiences of using the PEPA performance modelling tools with a non-repudiation protocol, in: Proc. 23rd European Simulation Multiconference, SCS Publishers, 2009.
- Y. Zhao and N. Thomas, A cost model analysis of a secure key distribution centre, in: Proc. Int'l Symposium on Trusted Computing, IEEE Computer Society, 2008.
- Y. Zhao and N. Thomas, Approximate solution of a PEPA model of a key distribution centre, in: Performance Evaluation - Metrics, Models and Benchmarks: SPEC Int'l Performance Evaluation Workshop, LNCS 5119, Springer Verlag, 2008.
- N. Thomas and Y. Zhao, Fluid flow analysis of a model of a secure key distribution centre, in: Proc. 24th UK Performance Engineering Workshop, Imperial College London, 2008.
Mobile ad hoc networks
- O. Younes and N. Thomas, Modelling and Performance Analysis of Multi-hop Ad Hoc Networks, Simulation: Practice and Theory, 38, pp. 69-97, 2013.
- O. Younes and N. Thomas, A Path Connection Availability Model for MANETs with Random Waypoint Mobility, in: Computer Performance Engineering: EPEW/UKPEW 2012, LNCS 7587, Springer, 2012.
- O. Younes and N. Thomas, SRN Models for Analysis of Multihop Wireless Ad Hoc Networks, in: Computer Performance Engineering: EPEW/UKPEW 2012, LNCS 7587, Springer, 2012.
- O. Younes and N. Thomas, Analysis of the Expected Number of Hops in Mobile Ad Hoc Networks with Random Waypoint Mobility, Electronic Notes in Theoretical Computer Science, 275, pp. 143-158, 2011.
- O. Younes and N. Thomas, An SRN model for IEEE 802.11 DCF MAC Protocol in Multi-hop Ad Hoc Networks with Hidden Nodes, The Computer Journal, 54(6), pp. 875-893, 2011.
- O. Younes and N. Thomas, SRN model for IEEE 802.11 DCF MAC Protocol in Multi-hop Ad Hoc Networks with Hidden Nodes, in: Proc. 26th UK Performance Engineering Workshop, University of Warwick, 2010.
- D. Cooper, P. Ezhilchelvan and I. Mitrani, Encounter-Based Message Propagation in Mobile Ad-Hoc Networks, Ad Hoc Networks Vol. 7, Issue 7, pp 1271-1284, Elsevier B.V., 2009.
- O. Younes, W. Elkilani and N. Thomas, SRN Model for Performance Evaluation of TCP Sessions Sharing Bottleneck Links in WAN, in: Proc. 23rd European Simulation Multiconference, SCS Publishers, 2009.
Resource management
- K. Gilly, C. Juiz, N. Thomas and R. Puigjaner, Adaptive admission control algorithm in a QoS-aware web system, Information Sciences, 199: 58-77, 2012.
- M. Mazzucco, I. Mitrani, J. Palmer, M. Fisher and P. McKee, Revenue maximization in web service provision, Computer Science - R&D 24(4): 211-224, 2009.
- J. Slegers, I. Mitrani and N. Thomas, Evaluating the optimal server allocation policy for clusters with on/off sources, Performance Evaluation, 66(8), pp. 453-467, 2009.
- J. Slegers, I. Mitrani and N. Thomas, Server allocation in grid systems with on/off sources, Annals of Operations Research, 170(1), pp. 251-263, 2009.
- X. Chen and N. Thomas, Investigating the performance of novel scheduling strategies, in: Proc. 25th UK Performance Engineering Workshop, University of Leeds, 2009.
- S. Martin and I. Mitrani, Analysis of job transfer policies in systems with unreliable servers, Annals of Operations Research Vol. 162, Issue 1, pp 127-141, Springer, 2008.
- N. Thomas, Comparing job allocation schemes where service demand is unknown, Journal of Computer and System Sciences, 74(6), pp. 1067-1081, 2008.
- M. Mazzucco, I. Mitrani, M. Fisher and P. McKee: Allocation and Admission Policies for Service Streams In 16th annual IEEE International Symposium on Modeling, Analysis, and Simulation of Computer and Telecommunication Systems (MASCOTS), September 8-10, 2008, Baltimore, MD, pp 155-162, IEEE, 2008.
- K. Gilly, C. Juiz, N. Thomas and R. Puigjaner, Scalable QoS content-aware load balancing algorithm for a Web Switch based on classical policies, in: Proc. 22nd IEEE Int'l Conference on Advanced Information Networking and Applications, pp. 934-941, IEEE Computer Society, 2008.
Scalable analysis techniques
- N. Thomas, A product-form solution for on-off components in PEPA, Performance and Security Modelling & Evaluation of Cooperative Heterogeneous Networks (HETNETS 2013), IFIP, 2013.
- N. Thomas and P. Harrison, Semi-product-form solution for PEPA models with functional rates, in: 20th International Conference on Analytical & Stochastic Modelling Techniques & Applications (ASMTA), LNCS 7984, pp. 416-430, Springer, 2013.
- N. Thomas, M. Harrison, Y. Zhao and X. Chen, Formal performance modelling: from protocols to people, in: Computer Performance Engineering: EPEW/UKPEW 2012, LNCS 7587, Springer, 2012.
- J. Bradley, N. Thomas, R. Hayden and A. Stefanek. Invited Response to Computer Journal Lecture by Prof. Jane Hillston. The Computer Journal 55(7):882-886, 2012.
- K. Kim and N. Thomasi, A fitting method with generalized Erlang distributions and its matrix interpretation, Simulation: Practice and Theory, 19(7), pp. 1507-1517, 2011.
- N. Thomas and Y. Zhao, Mean value analysis for a class of PEPA models, The Computer Journal, 54(5), pp. 643-652, 2011.
- P.G. Harrison and N. Thomas, Product form solution in PEPA via the reversed process, in: D. Kouvatsos (ed.) Network Performance Engineering - A Handbook on Convergent Multi-Service Networks and Next Generation Internet, LNCS 5233, Springer-Verlag, 2011.
- N. Thomas and J. Bradley, Analysis of non-product form parallel queues using a Markovian process algebra, in: D. Kouvatsos (ed.) Network Performance Engineering - A Handbook on Convergent Multi-Service Networks and Next Generation Internet, LNCS 5233, Springer-Verlag, 2011.
- I. Mitranii, Spectral Expansion Solutions for Markov-Modulated Queues. in: D. Kouvatsos (ed.) Network Performance Engineering - A Handbook on Convergent Multi-Service Networks and Next Generation Internet, LNCS 5233, Springer-Verlag, 2011.
- P.G. Harrison and N. Thomas, State dependent rates and semi-product form via the reversed process, in: Proc. 7th European Performance Engineering Workshop, Springer Verlag, 2010.
- N. Thomas, A. Marin and P. Harrison, Semi-product-form solution for models with state dependent rates, in: Proc. 9th Workshop on Process Algebra and Stochastically Timed Activities, Imperial College London, 2010.
- N. Thomas and J. Bradley, Analysis of non-product form parallel queues using a Markovian process algebra, in: D. Kouvatsos (ed.) Next Generation Internet: Performance Evaluation and Applications, LNCS 5233, Springer-Verlag, 2010.
- P.G. Harrison and N. Thomas, Product form solution in PEPA via the reversed process, in: D. Kouvatsos (ed.) Next Generation Internet: Performance Evaluation and Applications, LNCS 5233, Springer-Verlag, 2010.
- N. Thomas and Y. Zhao, Mean value analysis for a class of PEPA models, in: Computer Performance Evaluation: 6th European Performance Engineering Workshop, LNCS 5652, Springer Verlag, 2009.
- N. Thomas, Using ODEs from PEPA models to derive asymptotic solutions for a class of closed queueing networks, in: Proc. 8th Workshop on Process Algebra and Stochastically Timed Activities, University of Edinburgh, 2009.
Contact
School of Computing Science,
Newcastle University,
Newcastle upon Tyne, NE1 7RU
United Kingdom