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Dr Michael Howarth

Lecturer in Networking

Qualifications: MA MSc DPhil CEng MIEE

Email:
Phone: Work: 01483 68 3034
Room no: 10 BA 02

Further information

Research Interests

My research interests include IP quality of service, traffic engineering, multicast, and security and privacy, applied to fixed, satellite and wireless ad-hoc networks.

Further details can be found on my personal web page.

Publications

Highlights

  • Nadeem A, Howarth MP. (2011) 'Protection of MANETs from a range of attacks using an intrusion detection and prevention system'. Springer Telecommunication Systems, Online First, pp. 1-12.
    doi: 10.1007/s11235-011-9484-6
    Full text is available at: http://epubs.surrey.ac.uk/59955/
  • Papanagiotou I, Howarth MP. (2010) 'Delay-based quality of service through Intra-Domain Differentiated routing with optimised link weight setting'. IEEE Proceedings - IEEE Symposium on Computers and Communications, Riccione, Italy: IEEE Symposium on Computers and Communications (ISCC), 2010, pp. 622-627.
    doi: 10.1109/ISCC.2010.5546518
    Full text is available at: http://epubs.surrey.ac.uk/29737/

    Abstract

    The wide range of applications that are supported on the Internet requires it to deliver a diverse set of classes of service. For example, network providers need to support both delay-sensitive multimedia services and less time-sensitive applications such as web browsing and peer-to-peer transfers. Differentiated routing is one approach to delivering these different classes of service. In this paper we use an evolutionary algorithm to set link weights for our previously described Intra-Domain Differentiated Routing algorithm (IDDR) so as to optimise the delay differentiation between two classes of flows. In order to provide good robustness, the link weight setting is based on multiple traffic matrices. Results demonstrate that the delay for high QoS traffic is typically less than 60% of the delay for best effort traffic, and that this can be achieved across a wide range of traffic matrices. We also show that the delay differentiation is achieved by sending high QoS flows along paths that have fewer links and that those links have in general lower delay.

  • Howarth MP, Boucadair M, Flegkas P, Wang N, Pavlou G, Morand P, Coadic T, Griffin D, Asgari A, Georgatsos P. (2006) 'End-to-end quality of service provisioning through inter-provider traffic engineering'. ELSEVIER SCIENCE BV COMPUTER COMMUNICATIONS, 29 (6), pp. 683-702.
    doi: 10.1016/j.comcom.2005.07.022
    Full text is available at: http://epubs.surrey.ac.uk/59959/
  • Howarth MP, Iyengar S, Sun ZL, Cruickshank H. (2004) 'Dynamics of key management in secure satellite multicast'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, 22 (2), pp. 308-319.
    doi: 10.1109/JSAC.2003.819978
    Full text is available at: http://epubs.surrey.ac.uk/712098/
  • Sun Z, Howarth M, Cruickshank H, Iyengar S, Claverotte L. (2003) 'Networking issues in IP multicast over satellite'. INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, 21 (4-5), pp. 489-507.
    doi: 10.1002/sat.762
    Full text is available at: http://epubs.surrey.ac.uk/59958/

    Abstract

    This paper describes the issues that arise when using satellites for IP multicast, with the emphasis on multicast protocols and how their implementation depends on the satellite communications platform. Various link layer standards such as DVB-S, DVB-RCS and ATM can be used in satellites with on-board processing, and applied to meet user and network requirements for IP multicast. The paper provides an overview of the networking issues and their interactions. Specifically, we show how multicast networking protocols have to be modified to take into account the satellite link characteristics: these protocols include IGMP, multicast routing protocols and reliable multicast protocols. We also discuss how security systems support IP multicast.

Journal articles

  • Nadeem A, Howarth MP. (2011) 'Protection of MANETs from a range of attacks using an intrusion detection and prevention system'. Springer Telecommunication Systems, Online First, pp. 1-12.
    doi: 10.1007/s11235-011-9484-6
    Full text is available at: http://epubs.surrey.ac.uk/59955/
  • Amin M, Ho KH, Pavlou G, Howarth MP. (2009) 'A Closed-Loop Control Traffic Engineering System for the Dynamic Load Balancing of Inter-AS Traffic'. SPRINGER J NETW SYST MANAG, 17 (4), pp. 343-370.
    doi: 10.1007/s10922-009-9142-4
    Full text is available at: http://epubs.surrey.ac.uk/577006/
  • Boucadair M, Georgatsos P, Wang N, Griffin D, Pavlou G, Howarth MP, Elizondo A. (2009) 'The AGAVE approach for network virtualization: differentiated services delivery'. SPRINGER FRANCE ANN TELECOMMUN, 64 (5-6), pp. 277-288.
    doi: 10.1007/s12243-009-0103-4
    Full text is available at: http://epubs.surrey.ac.uk/711569/
  • Ho K-H, Pavlou G, Wang N, Howarth MP. (2009) 'Joint optimization of intra- and inter-autonomous system traffic engineering'. IEEE Transactions on Network and Service Management, 6 (2), pp. 64-79.
    doi: 10.1109/TNSM.2009.090601
  • Gonzalez O, Ansa G, Howarth MP, Pavlou G. (2008) 'Detection and accusation of packet forwarding misbehaviour in mobile ad-hoc networks'. Journal of Internet Engineering, 2 (1), pp. 181-192.
  • Wang N, Ho KH, Pavlou G, Howarth MP. (2008) 'An overview of routing optimization for Internet traffic engineering'. IEEE Communications Surveys and Tutorials, 10 (1), pp. 36-56.
    doi: 10.1109/COMST.2008.4483669
    Full text is available at: http://epubs.surrey.ac.uk/1819/
  • Ho KH, Howarth MP, Wang N, Pavlou G, Georgoulas S. (2007) 'Inter-autonomous system provisioning for end-to-end bandwidth guarantees'. ELSEVIER SCIENCE BV COMPUT COMMUN, 30 (18), pp. 3757-3777.
    doi: 10.1016/j.comcom.2007.09.008
  • Boucadair M, Levis A, Griffin D, Wang N, Howarth MP, Pavlou G, Mykoniati E, Georgatsos P, Quoitin B, Sanchez JR, Garcia-Osma ML. (2007) 'A framework for end-to-end service differentiation: Network planes and parallel internets'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE COMMUN MAG, 45 (9), pp. 134-143.
    doi: 10.1109/MCOM.2007.4342868
    Full text is available at: http://epubs.surrey.ac.uk/1670/
  • Griffin D, Spencer J, Griem J, Boucadair M, Morand P, Howarth MP, Wang N, Pavlou G, Asgari A, Georgatsos P. (2007) 'Interdomain routing through QoS-class planes'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE COMMUN MAG, 45 (2), pp. 88-95.
    doi: 10.1109/MCOM.2007.313401
    Full text is available at: http://epubs.surrey.ac.uk/1855/
  • Ng WHD, Howarth MP, Sun Z, Cruickshank H. (2007) 'Dynamic balanced key tree management for secure multicast communications'. IEEE Transactions on Computers, 56 (5), pp. 590-605.
    doi: 10.1109/TC.2007.1022
    Full text is available at: http://epubs.surrey.ac.uk/1827/
  • Howarth MP, Boucadair M, Flegkas P, Wang N, Pavlou G, Morand P, Coadic T, Griffin D, Asgari A, Georgatsos P. (2006) 'End-to-end quality of service provisioning through inter-provider traffic engineering'. ELSEVIER SCIENCE BV COMPUTER COMMUNICATIONS, 29 (6), pp. 683-702.
    doi: 10.1016/j.comcom.2005.07.022
    Full text is available at: http://epubs.surrey.ac.uk/59959/
  • Cruickshank H, Howarth MP, Iyengar S, Sun Z, Claverotte L. (2005) 'Securing multicast in DVB-RCS satellite systems'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 445 HOES LANE, PISCATAWAY, NJ 08855 USA IEEE WIRELESS COMMUNICATIONS, 12 (5), pp. 38-45.
    doi: 10.1109/MWC.2005.1522103
  • Howarth MP, Flegkas P, Pavlou G, Wang N, Trimintzios P, Griffin D, Griem J, Boucadair M, Morand P, Asgari AH, Georgatsos P. (2005) 'Provisioning for interdomain quality of service: the MESCAL approach'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE Communications Magazine, 43 (6), pp. 129-137.
    doi: 10.1109/MCOM.2005.1452841
    Full text is available at: http://epubs.surrey.ac.uk/60777/

    Abstract

    This article presents an architecture for supporting interdomain QoS across the multi-provider global Internet. While most research to date has focused on supporting QoS within a single administrative domain, mature solutions are not yet available for the provision of QoS across multiple domains administered by different organizations. The architecture described in this article encompasses the full set of functions required in the management (service and resource), control and data planes for the provision of end-to-end QoS-based IP connectivity services. We use the concept of QoS classes and show how these can be cascaded using service level specifications (SLSs) agreed between BGP peer domains to construct a defined end-to-end QoS. We illustrate the architecture by describing a typical operational scenario.

  • Howarth MP, Iyengar S, Sun ZL, Cruickshank H. (2004) 'Dynamics of key management in secure satellite multicast'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, 22 (2), pp. 308-319.
    doi: 10.1109/JSAC.2003.819978
    Full text is available at: http://epubs.surrey.ac.uk/712098/
  • Sun Z, Howarth M, Cruickshank H, Iyengar S, Claverotte L. (2003) 'Networking issues in IP multicast over satellite'. INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, 21 (4-5), pp. 489-507.
    doi: 10.1002/sat.762
    Full text is available at: http://epubs.surrey.ac.uk/59958/

    Abstract

    This paper describes the issues that arise when using satellites for IP multicast, with the emphasis on multicast protocols and how their implementation depends on the satellite communications platform. Various link layer standards such as DVB-S, DVB-RCS and ATM can be used in satellites with on-board processing, and applied to meet user and network requirements for IP multicast. The paper provides an overview of the networking issues and their interactions. Specifically, we show how multicast networking protocols have to be modified to take into account the satellite link characteristics: these protocols include IGMP, multicast routing protocols and reliable multicast protocols. We also discuss how security systems support IP multicast.

  • Howarth MP, Sun Z. (2003) 'Quantitative analysis of restricted reliability protocols for constant rate traffic'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE COMMUNICATIONS LETTERS, 7 (9), pp. 466-468.
    doi: 10.1109/LCOMM.2003.817336
    Full text is available at: http://epubs.surrey.ac.uk/60780/
  • Howarth MP, Cruickshank H, Sun Z. (2001) 'Unicast and multicast IP error performance over an ATM satellite link'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE COMMUNICATIONS LETTERS, 5 (8), pp. 340-342.
    doi: 10.1109/4234.940985
    Full text is available at: http://epubs.surrey.ac.uk/719208/

Conference papers

  • Soelistijanto B, Howarth MP. (2012) 'Traffic distribution and network capacity analysis in social opportunistic networks'. IEEE WiMob 2012 Proceedings, Barcelona, Spain: IEEE Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), Workshop on Selected Topics in Mobile and Wireless Computing (STWiMob), pp. 823-830.
    doi: 10.1109/WiMOB.2012.6379171
    Full text is available at: http://epubs.surrey.ac.uk/733320/

    Abstract

    Social opportunistic networks are intermittently connected mobile ad hoc networks (ICNs) that exploit human mobility to physically carry messages between disconnected parts of the network. Human mobility thus plays an essential role in the performance of forwarding protocols in the networks, and people's movements are in turn affected by their social interactions with each other. In this paper we present an analysis of the traffic distribution among the nodes of social opportunistic networks and its impact on network capacity. For our analysis, we use a human contact graph that represents a social network of individuals. We characterize the graph as a scale-free network and apply forwarding strategies based on the information required by a node to select relays for its messages, categorising this information either as isolated or complete network or local network knowledge. We use a social network property, centrality, for the forwarding strategies, additionally considering tie strength in the forwarding metric and investigate their impact on traffic distribution. We show that all the strategies result in unfair traffic distribution due to a strong non-random structure of the networks, where hub nodes process much more relay traffic than non-hub nodes. Finally, we present a mathematical model of network capacity as an upper-bound of network delivery performance where hub nodes' resources become the limiting factors, and show that including tie strength in the forwarding metric improves the network capacity.

  • Norouzi A, Howarth MP, Wang N. (2012) 'An ISP and end-user cooperative intradomain routing algorithm'. IEEE Cappadocia, Turkey: IEEE Symposium on Computers and Communications, pp. 000289-000294.
    doi: 10.1109/ISCC.2012.6249310
    Full text is available at: http://epubs.surrey.ac.uk/727755/

    Abstract

    The continuous growth in volume of Internet traffic, including VoIP, IPTV and user-generated content, requires improved routing mechanisms that satisfy the requirements of both the Internet Service Providers (ISPs) that manage the network and the end-users that are the sources and sinks of data. The objectives of these two players are different, since ISPs are typically interested in ensuring optimised network utilisation and high throughput whereas end-users might require a low-delay or a high-bandwidth path. In this paper, we present our UAESR (Utilisation-Aware Edge Selected Routing) algorithm, which aims to satisfy both players' demands concurrently by selecting paths that are a good compromise between the two players' objectives. We demonstrate by simulation that this algorithm allows both actors achieve their goals. The results support our argument that our cooperative approach achieves effective network resource engineering at the same time as offering routing flexibility and good quality of service to end-users.

  • Wang C, Wang N, Howarth MP, Pavlou G. (2011) 'An empirical study on the interactions between ALTO-assisted P2P overlays and ISP networks'. IEEE 2011 IEEE 36th Conference on Local Computer Networks (LCN), Bonn, Germany: 4th IEEE Workshop on Wireless and Internet Services, pp. 719-726.
    doi: 10.1109/LCN.2011.6115540
    Full text is available at: http://epubs.surrey.ac.uk/107401/

    Abstract

    The recently proposed Application Layer Traffic Optimization (ALTO) framework has opened up a new dimension for Internet traffic management that is complementary to the traditional application-agnostic traffic engineering (AATE) solutions currently employed by ISPs. In this paper, we investigate how ALTO-assisted Peer-to-Peer (P2P) traffic management functions interact with the underlying AATE operations, given that there may exist different application-layer policies in the P2P overlay. By considering specific P2P peer selection behaviors on top of a traffic-engineered ISP network, we conduct a performance analysis on how the application and network-layer respective performance is influenced by different policies at the P2P side. Our empirical study offers significant insight for the future design and analysis of cross-layer network engineering approaches that involve multiple autonomous optimization entities with both consistent and non-consistent policies.

  • Wang C, Wang N, Howarth MP, Pavlou G. (2010) 'On the interactions between non-cooperative P2P overlay and traffic engineering behaviors'. IEEE GLOBECOM - IEEE Global Telecommunications Conference, Miami, FL: IEEE Global Telecommunications Conference GLOBECOM 2010, 2010, pp. 1-6.
    doi: 10.1109/GLOCOM.2010.5683137
    Full text is available at: http://epubs.surrey.ac.uk/29739/

    Abstract

    Emerging Peer-to-Peer (P2P) technologies have enabled various types of content to be efficiently distributed over the Internet. Most P2P systems adopt selfish peer selection schemes in the application layer that in some sense optimize the user quality of experience. On the network side, traffic engineering (TE) is deployed by ISPs in order to achieve overall efficient network resource utilization. These TE operations are typically performed without distinguishing between P2P flows and other types of traffic. Due to inconsistent or even conflicting objectives from the perspectives of P2P overlay and network-level TE, the interactions between the two and their impact on the performance for each is likely to be non-optimal, and also has not yet been investigated in detail. In this paper we study such non-cooperative interactions by modeling best-reply dynamics, in which the P2P overlay and network-level TE optimize their own strategies based on the decision of the other player in the previous round. According to our simulations results based on data from the ABILENE network, P2P overlays exhibit strong resilience to adverse TE operations in maintaining end-to-end performance at the application layer. In addition, we show that network-level TE may suffer from performance deterioration caused by greedy peer (re-)selection behavior in reacting to previous TE adjustments.

  • Guo Y, Wang N, Howarth MP, Ho K-H. (2010) 'Link weight optimization for enhancing IP resilience using multi-plane routing'. IEEE Proceedings - IEEE Symposium on Computers and Communications, Riccione, Italy: IEEE Symposium on Computers and Communications (ISCC), 2010, pp. 899-905.
    doi: 10.1109/ISCC.2010.5546520
    Full text is available at: http://epubs.surrey.ac.uk/29738/

    Abstract

    With the increasing importance of the Internet for delivering personal and business applications, the slow re-convergence after network failure of existing routing protocols becomes a significant problem. This is especially true for real time multimedia services where service disruption cannot be generally tolerated. In order to ensure fast network failure recovery, IP Fast Reroute (FRR) can be adopted to immediately reroute affected customer traffic from the default path onto a backup path when link failure occurs, thus avoiding slow Interior Gateway Protocol (IGP) re-convergence. We notice that IGP link weight setting plays an important role in influencing the protection coverage performance in intra-domain link failures. Therefore in this paper we present an IGP link weight optimization scheme for backup path provisioning, which works on top of a multi-plane enabled routing platform. The scheme aims to optimize the path diversity among multiple routing planes. Due to the large search space of possible intra-domain link weights, in this paper we adopted a global search method based on a Genetic Algorithm to optimize the IGP link weights. Evaluation results show that in most cases a set of optimal link weights can be found which ensures that there are no more critical shared links among all the diverse paths on each routing plane. As a result, backup paths can be always available in case of single link failures.

  • Papanagiotou I, Howarth MP. (2010) 'Delay-based quality of service through Intra-Domain Differentiated routing with optimised link weight setting'. IEEE Proceedings - IEEE Symposium on Computers and Communications, Riccione, Italy: IEEE Symposium on Computers and Communications (ISCC), 2010, pp. 622-627.
    doi: 10.1109/ISCC.2010.5546518
    Full text is available at: http://epubs.surrey.ac.uk/29737/

    Abstract

    The wide range of applications that are supported on the Internet requires it to deliver a diverse set of classes of service. For example, network providers need to support both delay-sensitive multimedia services and less time-sensitive applications such as web browsing and peer-to-peer transfers. Differentiated routing is one approach to delivering these different classes of service. In this paper we use an evolutionary algorithm to set link weights for our previously described Intra-Domain Differentiated Routing algorithm (IDDR) so as to optimise the delay differentiation between two classes of flows. In order to provide good robustness, the link weight setting is based on multiple traffic matrices. Results demonstrate that the delay for high QoS traffic is typically less than 60% of the delay for best effort traffic, and that this can be achieved across a wide range of traffic matrices. We also show that the delay differentiation is achieved by sending high QoS flows along paths that have fewer links and that those links have in general lower delay.

  • Wang C, Wang N, Howarth MP, Pavlou G. (2010) 'A dynamic peer-to-peer traffic limiting policy for ISP networks'. IEEE Proceedings of the 2010 IEEE/IFIP Network Operations and Management Symposium, NOMS 2010, Osaka: Network Operations and Management Symposium (NOMS), 2010 IEEE, pp. 317-324.
    doi: 10.1109/NOMS.2010.5488483
    Full text is available at: http://epubs.surrey.ac.uk/71156/

    Abstract

    As a scalable paradigm for content distribution at Internet-wide scale, Peer-to-Peer (P2P) technologies have enabled a variety of networked services, such as distributed file-sharing and live video streaming. Most existing P2P systems employ nonintelligent peer selection algorithms for content swarming which greedily consume Internet bandwidth resources. As a result, Internet service providers (ISPs) need some efficient solutions for managing P2P traffic within their own networks. A common practice today is to block or shape P2P traffic in order to conserve bandwidth resources for carrying standard traffic from which revenue can be generated. In this paper, instead of looking at simple time-driven blocking/limiting approaches, we investigate how such types of limiting behaviors can be more gracefully performed by the ISP by taking into account the dynamics of both P2P traffic and of standard Internet traffic. Specifically, our approach is to adaptively limit excessive P2P traffic on critical network links that are prone to congestion, based on periodical link load/utilization measurements by the ISP. The ultimate objective is to guarantee non-P2P service capability while trying to accommodate as much P2P traffic as possible based on the available bandwidth resources. This approach can be regarded as a complementary solution to the recently proposed collaboration-based P2P paradigms such as P4P. Simulation results show that our approach not only eliminates performance degradation of non-P2P services that are caused by overwhelming P2P traffic, but also accommodates P2P traffic efficiently in both existing and future collaboration-based P2P network scenarios.

  • Wang N, Guo Y, Ho KH, Howarth MP, Pavlou G. (2009) 'Fast Network Failure Recovery Using Multiple BGP Routing Planes'. IEEE GLOBECOM 2009 - 2009 IEEE GLOBAL TELECOMMUNICATIONS CONFERENCE, VOLS 1-8, Honolulu, HI: IEEE Global Telecommunications Conference (GLOBECOM 09), pp. 3841-3846.
    doi: 10.1109/GLOCOM.2009.5425332
    Full text is available at: http://epubs.surrey.ac.uk/30851/

    Abstract

    We present an efficient multi-plane based fast network failure recovery scheme which can be realized using the recently proposed multi-path enabled BGP platforms. We mainly focus on the recovery scheme that takes into account BGP routing disruption avoidance at network boundaries, which can be caused by intra-AS failures due to the hot potato routing effect. On top of this scheme, an intelligent IP crank-back operation is also introduced for further enhancement of network protection capability against failures. Our simulations based on both real operational network topologies and synthetically generated ones suggest that, through our proposed optimized backup egress point selection algorithm, as few as two routing planes are able to achieve high degree of path diversity for fast recovery in any single link failure scenario.

  • Nadeem A, Howarth MP. (2009) 'A generalized intrusion detection & prevention mechanism for securing MANETs'. IEEE 2009 International Conference on Ultra Modern Telecommunications and Workshops, St. Petersburg: International Conference on ltra Modern Telecommunications & Workshops, 2009. ICUMT '09., pp. 1-6.
    doi: 10.1109/ICUMT.2009.5345400
    Full text is available at: http://epubs.surrey.ac.uk/59957/

    Abstract

    Most of the research in securing mobile ad hoc networks (MANETs) has focused on proposals which detect and prevent a specific kind of attack such as sleep deprivation, black hole, grey hole and rushing attacks. In this paper we broaden our previously developed algorithm AIDP and propose a generalized intrusion detection and prevention mechanism. We use a combination of anomaly-based and knowledge-based intrusion detection. This approach not only secures the MANET from a wide variety of routing attacks but also has the capability to detect new unforeseen attacks. Simulation results of a case study show that our proposed mechanism can successfully detect a variety of attacks, including multiple simultaneous different attacks, and identify and isolate the intruders with an affordable network overhead.

  • Nadeem A, Howarth MP. (2009) 'Adaptive intrusion detection and prevention of denial of service attacks in MANETs'. New York, USA : Association for Computing Machinery (ACM) Proceedings of the 2009 ACM International Wireless Communications and Mobile Computing Conference, IWCMC 2009, Leipzig, Germany: International Conference on Wireless Communication and Mobile Computing, pp. 926-930.
    doi: 10.1145/1582379.1582581
    Full text is available at: http://epubs.surrey.ac.uk/59956/

    Abstract

    Mobile ad-hoc networks (MANETs) are well known to be vulnerable to various attacks, due to features such as lack of centralized control, dynamic topology, limited physical security and energy constrained operations. In this paper we focus on preventing denial-of-service (DoS) attacks. As an example, we consider intruders that can cause DoS by exploiting the route discovery procedure of reactive routing protocols. We show the unsuitability of tools such as control chart, used in statistical process control (SPC), to detect DoS and propose an anomaly-based intrusion detection system that uses a combination of chi-square test & control chart to first detect intrusion and then identify an intruder. When the intruder is isolated from the network we show reduced overhead and increased throughput. Simulation results show that AIDP performs well at an affordable processing overhead over the range of scenarios tested.

  • Wang CJ, Wang N, Howarth MP, Pavlou G. (2009) 'An adaptive peer selection scheme with dynamic network condition awareness'. IEEE 2009 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, VOLS 1-8, Dresden, Germany: IEEE International Conference on Communications (ICC 2009), pp. 2293-2297.
    doi: 10.1109/ICC.2009.5198715
    Full text is available at: http://epubs.surrey.ac.uk/71159/

    Abstract

    Locality-based peer selection paradigms have been proposed recently based on cooperation between peer-to-peer (P2P) service providers, Internet Service Providers (ISPs) and end users in order to achieve efficient resource utilization by P2P traffic. Based on this cooperation between different stakeholders, we introduce a more advanced paradigm with adaptive peer selection that takes into account traffic dynamics in the operational network. Specifically, peers associated with low path utilization as measured by the ISP are selected in order to reduce the probability of network congestion. This approach not only improves real-time P2P service assurance but also optimizes the overall use of network resources. Our simulations based on the GEANT network topology and real traffic traces show that the proposed adaptive peer selection scheme achieves significant improvement in utilizing bandwidth resources as compared to static locality-based approaches.

  • Duque OFG, Hadjiantonis AM, Pavlou G, Howarth MP. (2009) 'Adaptable Misbehavior Detection and Isolation in Wireless Ad Hoc Networks Using Policies'. IEEE 2009 IFIP/IEEE INTERNATIONAL SYMPOSIUM ON INTEGRATED NETWORK MANAGEMENT (IM 2009) VOLS 1 AND 2, New York, NY: IFIP/IEEE International Symposium on Integrated Network Management (IM 2009), pp. 242-250.
    doi: 10.1109/INM.2009.5188816
    Full text is available at: http://epubs.surrey.ac.uk/31389/

    Abstract

    Wireless ad hoc networks provide the communications platform for new technologies and applications, such as vehicular ad hoc networks or wireless mesh networks. However, their multihop wireless nature makes them inherently unreliable and vulnerable, since their overall performance depends on the cooperative packet forwarding behavior of each individual node. In this paper we present a role-based approach that uses a distributed management overlay and gathers information about the packet forwarding activities of each node in the network. Using policies to control an adaptive algorithmic method that monitors the individual behavior of each node, we show that it is possible to detect, accuse and punish misbehaving nodes with a high degree of confidence. Our evaluation results demonstrate that after the successful detection of misbehaving nodes, their punishment through network isolation can significantly improve network performance in terms of packet delivery and throughput.

  • Wang CJ, Wang N, Howarth MP. (2009) 'A New Approach for Achieving Traffic-Exchange Localization in P2P-based Content Distribution'. IEEE 2009 INTERNATIONAL CONFERENCE ON TELECOMMUNICATIONS (ICT), Marrakech, MOROCCO: 16th International Conference on Telecommunications (ICT), pp. 59-64.
    doi: 10.1109/ICTEL.2009.5158619
    Full text is available at: http://epubs.surrey.ac.uk/31427/

    Abstract

    Due to the fact that P2P applications have dominantly accounted for the entire Internet traffic, how to efficiently manage P2P traffic has become increasingly important. It has been recently proposed that the underlying network information can be shared between ISPs and P2P service providers in order to achieve efficient resource utilization, with the locality-based peer selection being a specific example. Based on such collaboration, we propose a proportional traffic-exchange localization scheme for making efficient use of network resources. Our approach employs locality information in order to regulate the volume of traffic exchange between peers according to their physical distance between peers. The key objective of our approach is to further reduce both intra- and inter-autonomous system (AS) traffic compared with basic locality-based peer selection solutions. Our simulation-based results have shown that this approach is not only able to reduce a significant of inter-AS P2P traffic, but also to balance the network utilization in comparison to existing approaches.

  • Papanagiotou I, Howarth MP. (2008) 'Intra-Domain Delay-Based Quality of Service Using Differentiated Routing'. SPRINGER-VERLAG BERLIN MANAGEMENT OF CONVERGED MULTIMEDIA NETWORKS AND SERVICES, PROCEEDINGS, Samos, GREECE: 11th IFIP/IEEE International Conference on Management of Multimedia and Mobile Networks and Services 5274, pp. 127-138.
    doi: 10.1007/978-3-540-87359-4_12
    Full text is available at: http://epubs.surrey.ac.uk/31783/

    Abstract

    Differentiated routing is an approach to providing service differentiation in networks, a field that is currently receiving significant research attention. In this report we present an algorithm, namely Intra-Domain Differentiated Routing (IDDR), which supports qualitative delay differentiation in IP networks. We review existing differentiated routing approaches and then introduce IDDR and present initial results. We demonstrate that using IDDR we can achieve qualitative delay differentiation for two classes of flows.

  • Amin M, Ho KH, Wang N, Howarth MP, Pavlou G. (2008) 'Making IP traffic engineering robust to intra- and inter-AS transient link failures'. IEEE 2008 IEEE NETWORK OPERATIONS AND MANAGEMENT SYMPOSIUM, VOLS 1 AND 2, Salvador, BRAZIL: IEEE Network Operations and Management Symposium, pp. 81-88.
    doi: 10.1109/NOMS.2008.4575120
    Full text is available at: http://epubs.surrey.ac.uk/60779/
  • Guo Y, Wang N, Ho KH, Howarth MP, Pavlou G. (2008) 'Achieving Fast BGP Reroute with Traffic Engineering Using Multiple Routing Planes'. SPRINGER-VERLAG BERLIN IP OPERATIONS AND MANAGEMENT, PROCEEDINGS, Samos, GREECE: 8th IEEE International Workshop on IP Operations and Management 5275 (LNCS), pp. 41-52.
    doi: 10.1007/978-3-540-87357-0_4
    Full text is available at: http://epubs.surrey.ac.uk/727763/

    Abstract

    In today’s BGP routing architecture, traffic delivery is in general based on single path selection paradigms. The lack of path diversity hinders the support for resilience, traffic engineering and QoS provisioning across the Internet. Some recently proposed multi-plane extensions to BGP offer a promising mechanism to enable diverse inter-domain routes towards destination prefixes. Based on these enhanced BGP protocols, we propose in this paper a novel technique to enable controlled fast egress router switching for handling network failures. In order to minimize the disruptions to real-time services caused by the failures, backup egress routers can be immediately activated through locally remarking affected traffic towards alternative routing planes without waiting for IGP routing re-convergence. According to our evaluation results, the proposed multi-plane based egress router selection algorithm is able to provide both high path diversity and balanced load distribution across inter-domain links with a small number of planes.

  • Gonzalez OF, Howarth MP, Pavlou G. (2007) 'Detection of packet forwarding misbehavior in mobile ad-hoc networks'. SPRINGER-VERLAG BERLIN Wired/Wireless Internet Communications, Proceedings, Coimbra, PORTUGAL: 5th International Conference on Wired/Wireless Internet Communications 4517, pp. 302-314.
    doi: 10.1007/978-3-540-72697-5_26
  • Gonzalez OF, Howarth MP, Pavlou G. (2007) 'An algorithm to detect packet forwarding misbehavior in mobile Ad-Hoc networks'. IEEE 2007 10TH IFIP/IEEE INTERNATIONAL SYMPOSIUM ON INTEGRATED NETWORK MANAGEMENT (IM 2007), VOLS 1 AND 2, Munich, GERMANY: 10th IFIP/IEEE International Symposium on Integrated Network Management, pp. 813-816.
    doi: 10.1109/INM.2007.374720
    Full text is available at: http://epubs.surrey.ac.uk/2057/
  • Wang N, Griffin D, Spencer J, Griem J, Sanchez JR, Boucadair M, Mykoniati E, Quoitin B, Howarth MP, Pavlou G. (2007) 'A framework for lightweight QoS provisioning: Network planes and parallel Internets'. IEEE 2007 10TH IFIP/IEEE INTERNATIONAL SYMPOSIUM ON INTEGRATED NETWORK MANAGEMENT (IM 2007), VOLS 1 AND 2, Munich, GERMANY: 10th IFIP/IEEE International Symposium on Integrated Network Management, pp. 797-800.
    doi: 10.1109/INM.2007.374716
    Full text is available at: http://epubs.surrey.ac.uk/2278/
  • Elizondo AJ, Garcia Osma ML, Rodriguez Sanchez J, Boucadair M, Wang N, Howarth MP, Pavlou G, Quoitin B. (2006) 'On the creation of network planes'. Geneva, Switzerland: EU IST Broadband Europe Conference
    Full text is available at: http://epubs.surrey.ac.uk/726625/
  • Ho KH, Howarth MP, Wang N, Pavlou G, Georgoulas S. (2006) 'Joint Optimization of Intra- and Inter-Autonomous System Traffic Engineering'. IEEE 2006 IEEE/IFIP NETWORK OPERATIONS AND MANAGEMENT SYMPOSIUM, VOLS 1 AND 2, Vancouver, CANADA: IEEE/IFIP Network Operations and Management Symposium, pp. 248-259.
    doi: 10.1109/NOMS.2006.1687556
    Full text is available at: http://epubs.surrey.ac.uk/719210/
  • Amin M, Ho KH, Howarth MP, Pavlou G. (2006) 'Making outbound route selection robust to egress point failure'. SPRINGER-VERLAG BERLIN NETWORKING 2006: Networking Technologies, Services, Protocols; Performance of Computer and Communication Networks; Mobile and Wireless Communications Systems, Coimbra, PORTUGAL: 5th International IFIP-TC6 Networking Conference 3976, pp. 233-246.
    doi: 10.1007/11753810_20
    Full text is available at: http://epubs.surrey.ac.uk/280478/

    Abstract

    Offline inter-domain outbound Traffic Engineering (TE) can be formulated as an optimization problem whose objective is to determine primary egress points for traffic exiting a domain. However, when egress point failures happen, congestion may occur if secondary egress points are not carefully determined. In this paper, we formulate a bi-level outbound TE problem in order to make outbound route selection robust to egress point failures. We propose a tabu search heuristic to solve the problem and compare the performance to three alternative approaches. Simulation results demonstrate that the tabu search heuristic achieves the best performance in terms of our optimization objectives and also keeps traffic disruption to a minimum.

  • Amin M, Ho KH, Howarth MP, Pavlou G. (2006) 'An integrated network management framework for inter-domain outbound traffic engineering'. SPRINGER-VERLAG BERLIN AUTONOMIC MANAGEMENT OF MOBILE MULTIMEDIA SERVICES, PROCEEDINGS, Dublin, IRELAND: 9th IFIP/IEEE International Conference on Management of Multimedia and Mobile Networks and Services S 4267, pp. 208-222.
    doi: 10.1007/11907381_21
    Full text is available at: http://epubs.surrey.ac.uk/726626/

    Abstract

    This paper proposes an integrated network management framework for inter-domain outbound traffic engineering. The framework consists of three functional blocks (monitoring, optimization and implementation) to make the outbound traffic engineering adaptive to network condition changes such as inter-domain traffic demand variation, inter-domain routing changes and link failures. The objective is to keep the inter-domain link utilization balanced under any of these changes while reducing service disruptions and reconfiguration overheads. Simulation results demonstrate that the proposed framework can achieve better load balancing with less service disruptions and re-configuration overheads in comparison to alternative approaches.

  • Amin M, Pavlou G, Howarth MP, Ho KH. (2005) 'Improving survivability through traffic engineering in MPLS networks'. Proceedings of 10th IEEE Symposium on Computers and Communications, Cartagena: IEEE Symposium on Computers and Communications, pp. 758-763.
    doi: 10.1109/ISCC.2005.84
    Full text is available at: http://epubs.surrey.ac.uk/1851/

    Abstract

    The volume of higher priority Internet applications is increasing as the Internet continues to evolve. Customers require quality of service (QoS) guarantees with not only guaranteed bandwidth and delay but also with high availability. Our objective is for each estimated traffic flow to find a primary path with improved availability and minimum failure impact while satisfying bandwidth constraints and also minimizing network resource consumption. We devise a heuristic algorithm with four different cost functions to achieve our objective. Our approach can enhance availability of primary paths, reduce the effect of failure and also reduce the total resource consumption for both primary and backup paths.

  • Cruickshank HS, Howarth MP, Iyengar S, Sun Z. (2005) 'A comparison between satellite DVB conditional access and secure IP multicast'. Dresden, Germany: 14th IST Mobile and Wireless Communications Summit
    Full text is available at: http://epubs.surrey.ac.uk/719394/

    Abstract

    Security of satellite data is becoming an important issue. The DVB (TV broadcasting) Conditional Access system used in satellite broadcasting has however been surrounded by controversy for many years due to the spread of counterfeit smart cards, and this paper examines the weaknesses of current DVB-S security. We provide an alternative solution to secure multicast services over satellites using IPSEC and a group key management system called GSAKMP.

  • Ho KH, Howarth MP, Wang N, Pavlou G, Georgoulas S. (2005) 'Two approaches to Internet traffic engineering for end-to-end quality of service provisioning'. IEEE Rome: 1st EuroNGI Conference on Next Generation Internet Networks - Traffic Engineering
    Full text is available at: http://epubs.surrey.ac.uk/719428/
  • Howarth MP, Flegkas P, Pavlou G, Trimintzios P, Asgari H, Griffin D, Griem J, Boucadair M, Georgatsos P. (2005) 'An architectural framework for inter-domain quality of service provisioning'. Nice, France: IFIP/IEEE International Symposium on Integrated Network Management (IM2005)
    Full text is available at: http://epubs.surrey.ac.uk/719395/

    Abstract

    This paper presents an architecture that supports inter-domain quality of service (QoS) across the multi-provider commercial Internet. The architecture describes the full set of functions in the management, control and data planes required for network providers to work together to deliver end-to-end QoS-based IP connectivity services. We use the concept of QoS Classes and show how these can be combined together using service level specifications (SLSs) agreed between adjacent domains to construct a defined end-to-end QoS that is supported across multiple domains.

  • Asgari A, Boucadair M, Egan R, Morand P, Griffin D, Griem J, Georgatsos P, Spencer J, Pavlou G, Howarth MP. (2005) 'Inter-provider QoS peering for IP service offering across multiple domains'. Springer Waterloo, Ontario, Canada: 2nd International Workshop on Next Generation Networking Middleware (NGNM05)
    Full text is available at: http://epubs.surrey.ac.uk/297619/
  • Ho KH, Wang N, Trimintzios P, Pavlou G, Howarth MP. (2004) 'On egress router selection for inter-domain traffic with bandwidth guarantees'. IEEE Phoenix, Arizona, US: IEEE Workshop on High Performance Switching and Routing, pp. 337-342.
    doi: 10.1109/HPSR.2004.1303504
    Full text is available at: http://epubs.surrey.ac.uk/297620/

    Abstract

    As the Internet has grown in size and diversity of applications, the next generation is designed to accommodate flows that span over multiple domains with quality of service guarantees, and in particular bandwidth. In that context, a problem emerges when destinations for inter-domain traffic may be reachable through multiple egress routers. Selecting different egress routers for traffic flows can have diverse effects on network resource utilization. In this paper, we address a critical provisioning issue of how to select an egress router that satisfies the customer end-to-end bandwidth requirement while minimizing the total bandwidth consumption in the network.

  • Ho KH, Pavlou G, Howarth MP, Wang N. (2004) 'An incentive-based quality of service aware algorithm for offline inter-AS traffic engineering'. IEEE 2004 IEEE Workshop on IP Operations and Management Proceedings (IPOM 2004), Beijing, PEOPLES R CHINA: IEEE International Workshop on IP Operations and Management, pp. 34-40.
    doi: 10.1109/IPOM.2004.1547589
    Full text is available at: http://epubs.surrey.ac.uk/2061/
  • Liang L, Sun Z, Howarth MP. (2003) 'Measurement and modelling of WWW traffic in a LAN environment'. Ljubliana, Slovenia: EUROCON
    doi: 10.1109/EURCON.2003.1248059
  • Cruickshank H, Howarth MP, Iyengar S, Sun Z. (2003) 'Key management and multi-layer IPSEC for satellite multicast'. Noordwijk, The Netherlands: Joint EU COST272-COST280 Workshop (Cooperation in the Field of Science and Technology)
    Full text is available at: http://epubs.surrey.ac.uk/733390/
  • Sun Z, Cruickshank H, Iyengar S, Howarth MP, Claverotte L, Gomez R. (2003) 'IP multicast over satellite'. AIAA Yokohama, Japan: AIAA International Communication Satellite Systems Conference
    doi: 10.2514/6.2003-2378
    Full text is available at: http://epubs.surrey.ac.uk/726627/
  • Cruickshank H, Iyengar S, Howarth MP, Sun Z, Zeppenfeldt F, Kenny G. (2003) 'Secure IP multicast over satellites'. Sophia Antipolis, France: ETSI Broadband Satellite Multimedia (BSM) Working Group
    Full text is available at: http://epubs.surrey.ac.uk/729422/
  • Howarth MP, Iyengar S, Cruickshank H, Sun Z. (2002) 'Security systems for multicast data transfer over satellite'. Guildford, Surrey: COST272 Workshop
    Full text is available at: http://epubs.surrey.ac.uk/726628/
  • Cruickshank H, Iyengar S, Howarth MP, Sun Z. (2002) 'Securing satellite communications'. IEE Savoy Place, London: IEE Military Satellite Communications Seminar
  • Annoni M, Boiero G, Salis N, Cruickshank HS, Howarth MP, Sun Z. (2002) 'Interworking between multi-layer IPSEC and secure multicast services over GEO satellites'. Thessaloniki, Greece: COST272 Workshop
    Full text is available at: http://epubs.surrey.ac.uk/726629/
  • Sun Z, Cruickshank H, Iyengar S, Howarth MP, Claverotte L, de la Plaza J. (2002) 'IP multicast over satellites - technology challenges'. American Institute of Aeronautics and Astronautics Montreal, Canada: AIAA International Communication Satellite Systems Conference
    doi: 10.2514/MICSSC02
    Full text is available at: http://epubs.surrey.ac.uk/726630/
  • Howarth MP, Sun Z. (2002) 'Performance of an IP reliable multicast protocol over a GEO satellite ATM link'. American Institute of Aeronautics and Astronautics Montreal, Canada: AIAA International Communication Satellite Systems Conference
    doi: 10.2514/6.2002-1876
    Full text is available at: http://epubs.surrey.ac.uk/719209/

Reports

  • Boucadair M, Morand P, Levis P, Coadic T, Asgari H, Georgatsos P, Griffin D, Spencer D, Howarth MP. (2005) QoS-Enhanced Border Gateway Protocol. in (ed.) IETF Internet Draft Article number draft-boucadair-qos-bgp-spec-01
    Full text is available at: http://epubs.surrey.ac.uk/733391/

Teaching

Full details including lecturing and project supervision are on my personal web page.

Publications (2)

Many of my papers are available under open access at Surrey Research Insight; and a more complete and up to date list of publications, including published versions where copyright permits, is on my personal web page.