Distributed Systems and Networks Laboratory

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Current research within this laboratory includes a broad range of inter-disciplinary topics that span mathematics, computer science and physics, with emphasis on adaptive distributed communication systems:

  • Mathematical modelling of communications networks
  • Adaptive network architectures
  • Large-scale mobility support
  • Mobile ad hoc networks
  • Vehicular ad hoc networks
  • Game-theoretic protocols
  • Biologically inspired protocols

Research showcase

Networking research with the OPNET Modeler

The OPNET Modeler is being used in two on-going PhD research projects on Intelligent Transporation Systems (ITS) and topology control in wireless networks:

  1. Topology Control and Routing in Wireless Networks (student: Miss Amalia Tsanaka)

    Decentralised wireless networks are emerging as an important technological development that has the potential to influence our world: Ad hoc emergency response team communications support in areas where the local communications infrastructure is decimated, extensive environmental monitoring and early warning system, and automated highways all depend on our ability to make such networks work. A limiting factor in their operation is usually the battery life of the network node equipment. This project examines how to bring together ways of controlling the flow of data over such networks simultaneously with minimising the intra-network interference and maximising the network battery-dependent lifetime.

    This research programme employs analogies between the propagation of light rays in graded index media to determine geographic routing forwarding paths in wireless sensor networks that are displaced from the geodesics dictated by greedy routing techniques, away from geographical areas containing nodes with depleted battery. This is achieved by setting up an approximate spatial battery stored energy field distribution which is treated in an analogous manner to a spatial refractive index distribution. OPNET simulations are used to quantify the resulting increased network lifetime.
  2. Routing framework for vehicular ad hoc networks: Regional dissemination of data using a directional restricted broadcasting technique (student: Ms Debra Topham)

    This project aims to create a routing framework to support inter-vehicle communication underpinning intelligent transportation systems applications. The routing framework consists of a variety of appropriate techniques from the area of mobile ad hoc networks. The PhD concentrated on the trade-offs that need to be made in order to create an efficient, reliable broadcast mechanism to a specified geographical region along a highway.

    OPNET is being used to evaluate the reliability of such the proposed geocasting protocol and characterise the associated message dissemination delays that might affect adversely the operation of safety-critical ITS applications.

The Local Network Abridgement (LNA) Procedure

The Logical Network Abridgement procedure is a novel iterative method of summarising the topology diversity of complex networks that can be used for diversity routing, network resiliency planning and examining the natural community/clustering structure of networks.

Logical Network Abridgement
Map of the internet as of 15th of January 2006


Pictured above: Internet map as of 16th January 2006


net, ca, us
com, org
mil, gov, edu
jp, cn, tw, au
de, uk, it, pl, fr
br, kr, nl



Academic staff

  • Dr Costas Constantinou - Head of DSNL laboratory

Research staff

  • Mr Paul Kiddie - Distributed security in peer-to-peer networks based on game-theoretic and immunological principles

PhD/MPhil students

  • Miss Amalia Tsanaka - Joint Topology Control and Routing in Mobile Ad Hoc Networks
  • Miss Debra Topham - Investigation into the use of ad hoc networks in Intelligent Transportation Systems (sponsored by MIRA Ltd.)
  • Mr Seyed Hani ElaMahdi Mortazavi Najafabadi - Game Theoretic Approach to Medium Access Control Protocol (MAC) in Wireless Networks



'Towards a Science of Networks' workshop

The aim of this workshop was to define a set of grand challenges on Communication Systems and Complexity.


Selected publications

Journal papers


Liu Z., Kwiatkowska M. and Constantinou C., 'A Self-Organised Emergent Routing Mechanism for Mobile Ad Hoc Networks', European Transactions on Telecommunications, 16, 457-470, 2005

Stepanenko A. S., Constantinou C. C. and Arvanitis T. N., 'Large-Scale Behaviour of Packet-Switched Networks: Theoretical Analysis Framework', Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 461, 933-955, 2005


Ji L, Arvanitis T. N. and Constantinou C. C., 'Game Theoretic Approach for Resource Allocation in Diffserv Networks', Annals of Mathematics, Computing and Teleinformatics, 2, 73-79, 2004


Stepanenko A., Constantinou C. C., Arvanitis T. N. and Baughan K., 'On the statistical properties of core network internet traffic', Electronics Letters, 38, 350-351, 2002

Conference papers


Topham D. A., Ward D., Du J., Arvanitis T. N. and Constantinou C. C., 'Routing Framework for Vehicular Ad Hoc Networks: Regional Dissemination of Data Using a Directional Restricted Broadcasting Technique', Proceedings of 2nd International Workshop on Intelligent Transportation (WIT’05), 23-28, 2005

Liu Z., Kwiatkowska M. and Constantinou C., 'A Biologically Inspired Congestion Control Routing Algorithm for MANETs', In Proc. IEEE PerCom International Workshop on Pervasive Wireless Networking (IEEE PWN'05), Third IEEE Conference on Pervasive Computing and Communications Workshops, 226-231, 2005

Topham D. A., Ward D., Constantinou C. C. and Arvanitis T. N., 'Developments in vehicle to vehicle communications', Proceedings of Advanced Microsystems for Automotive Applications 2005 (AMAA 2005, Valldorf J. and Gessner W. (Eds.), Advanced Microsystems for Automotive Applications 2005 (VDI-Buch Berlin: Springer-Verlag, 353-370, 2005

Liu Z., Kwiatkowska M. and Constantinou C, 'A Biologically Inspired QoS Routing Algorithm for Mobile Ad Hoc Networks', Proc. 19th International Conference on Advanced Information Networking and Applications (AINA 2005), 426-331, 2005


Liu Z., Kwiatkowska M. and Constantinou C., 'A Swarm Intelligence Inspired Routing Algorithm for Mobile Ad Hoc Networks', Proceedings 3rd IASTED International Conference on Communications, Internet and Information Technology (CIIT'04), ACTA Press, 2004


Topham D. A., Ward D., Arvanitis T. N. and Constantinou C. C., 'Inter-vehicle communications based on mobile ad hoc networks', Proceedings of the 1st IEE International Conference on Sensors, Navigation and Communications for Vehicle Telematics (VehCom 2003), 135-140, 2003


Stepanenko A., Constantinou C. C., Arvanitis T. N. and Baughan K., 'On a theory of interacting queues', Proceedings of Networking 2002, Lecture notes in Computer Science ( LNCS2345), New York: Springer-Verlag, 769-777, 2002

Patent applications

  • C. C. Constantinou, K. Baughan, A. S. Stepanenko, T. N. Arvanitis. 2003. Data Communication Network, UK Patent application GB-0306855.8.
  • K. Baughan, C. C. Constantinou, T. N. Arvanitis, A. S. Stepanenko. 2004. Data Communication Network, PCT/EP2004/050195