References of "Martin, Sylvain"
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See detailOutbound SPIT Filter with Optimal Performance Guarantees
Jung, Tobias ULg; Martin, Sylvain ULg; Nassar, Mohamed et al

in Computer Networks (2013), 57(7), 16301643

This paper presents a formal framework for identifying and filtering SPIT calls (SPam in Internet Telephony) in an outbound scenario with provable optimal performance. In so doing, our work is largely ... [more ▼]

This paper presents a formal framework for identifying and filtering SPIT calls (SPam in Internet Telephony) in an outbound scenario with provable optimal performance. In so doing, our work is largely different from related previous work: our goal is to rigorously formalize the problem in terms of mathematical decision theory, find the optimal solution to the problem, and derive concrete bounds for its expected loss (number of mistakes the SPIT filter will make in the worst case). This goal is achieved by considering an abstracted scenario amenable to theoretical analysis, namely SPIT detection in an outbound scenario with pure sources. Our methodology is to first define the cost of making an error (false positive and false negative), apply Wald’s sequential probability ratio test to the individual sources, and then determine analytically error probabilities such that the resulting expected loss is minimized. The benefits of our approach are: (1) the method is optimal (in a sense defined in the paper); (2) the method does not rely on manual tuning and tweaking of parameters but is completely self-contained and mathematically justified; (3) the method is computationally simple and scalable. These are desirable features that would make our method a component of choice in larger, autonomic frameworks. [less ▲]

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See detailContextual Multi-armed Bandits for the Prevention of Spam in VoIP Networks
Jung, Tobias ULg; Martin, Sylvain ULg; Ernst, Damien ULg et al

E-print/Working paper (2012)

In this paper we argue that contextual multi-armed bandit algorithms could open avenues for designing self-learning security modules for computer networks and related tasks. The paper has two ... [more ▼]

In this paper we argue that contextual multi-armed bandit algorithms could open avenues for designing self-learning security modules for computer networks and related tasks. The paper has two contributions: a conceptual one and an algorithmical one. The conceptual contribution is to formulate -- as an example -- the real-world problem of preventing SPIT (Spam in VoIP networks), which is currently not satisfyingly addressed by standard techniques, as a sequential learning problem, namely as a contextual multi-armed bandit. Our second contribution is to present CMABFAS, a new algorithm for general contextual multi-armed bandit learning that specifically targets domains with finite actions. We illustrate how CMABFAS could be used to design a fully self-learning SPIT filter that does not rely on feedback from the end-user (i.e., does not require labeled data) and report first simulation results. [less ▲]

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See detailDISco: a Distributed Information Store for Network Challenges and Their Outcome
Martin, Sylvain ULg; Chiarello, Laurent ULg; Leduc, Guy ULg

in Keeney, John; Serrat, Joan (Eds.) 5th International workshop on Distributed Autonomous Network Management Systems (2012, April)

We present the design of DISco, a storage and communication middleware that enables distributed and task-centric autonomic control of networks. DISco allows multi-agent identification of anomalous ... [more ▼]

We present the design of DISco, a storage and communication middleware that enables distributed and task-centric autonomic control of networks. DISco allows multi-agent identification of anomalous situations (challenges) and assists coordinated remediation that will maintain service at an acceptable level, although degraded. The history of agents decisions, their context and outcomes is tracked as the situation evolves, and information is automatically gathered and organised to ease further human-assisted diagnosis. We then explore the feasibility of using state of the art peer-to-peer publish/subscribe and storage systems as building blocks for this service. The ability of those systems to support range queries and aggregation will be a key factor for their suitability to the task. [less ▲]

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See detailDISco: a Distributed Information Store for network Challenges and their Outcome
Martin, Sylvain ULg; Chiarello, Laurent ULg; Leduc, Guy ULg

Report (2012)

We present DISco, a storage and communication middleware designed to enable distributed and task-centric autonomic control of networks. DISco is designed to enable multi-agent identification of anomalous ... [more ▼]

We present DISco, a storage and communication middleware designed to enable distributed and task-centric autonomic control of networks. DISco is designed to enable multi-agent identification of anomalous situations -- so-called "challenges" -- and assist coordinated remediation that maintains degraded -- but acceptable -- service level, while keeping a track of the challenge evolution in order to enable human-assisted diagnosis of flaws in the network. We propose to use state-of-art peer-to-peer publish/subscribe and distributed storage as core building blocks for the DISco service. [less ▲]

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See detailSPRT for SPIT: Using the Sequential Probability Ratio Test for Spam in VoIP Prevention
Jung, Tobias ULg; Martin, Sylvain ULg; Ernst, Damien ULg et al

in Proc. of 6th International Conference on Autonomous Infrastructure, Management and Security (2012)

This paper presents the first formal framework for identifying and filtering SPIT calls (SPam in Internet Telephony) in an outbound scenario with provable optimal performance. In so doing, our work ... [more ▼]

This paper presents the first formal framework for identifying and filtering SPIT calls (SPam in Internet Telephony) in an outbound scenario with provable optimal performance. In so doing, our work deviates from related earlier work where this problem is only addressed by ad-hoc solutions. Our goal is to rigorously formalize the problem in terms of mathematical decision theory, find the optimal solution to the problem, and derive concrete bounds for its expected loss (number of mistakes the SPIT filter will make in the worst case). This goal is achieved by considering a scenario amenable to theoretical analysis, namely SPIT detection in an outbound scenario with pure sources. Our methodology is to first define the cost of making an error, apply Wald’s sequential probability ratio test, and then determine analytically error probabilities such that the resulting expected loss is minimized. The benefits of our approach are: (1) the method is optimal (in a sense defined in the paper); (2) the method does not rely on manual tuning and tweaking of parameters but is completely self-contained and mathematically justified; (3) the method is computationally simple and scalable. These are desirable features that would make our method a component of choice in larger, autonomic frameworks. [less ▲]

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See detailContextual Multi-armed Bandits for Web Server Defense
Jung, Tobias ULg; Martin, Sylvain ULg; Ernst, Damien ULg et al

in Hussein, Abbas (Ed.) Proceedings of 2012 International Joint Conference on Neural Networks (IJCNN) (2012)

In this paper we argue that contextual multi-armed bandit algorithms could open avenues for designing self-learning security modules for computer networks and related tasks. The paper has two ... [more ▼]

In this paper we argue that contextual multi-armed bandit algorithms could open avenues for designing self-learning security modules for computer networks and related tasks. The paper has two contributions: a conceptual and an algorithmical one. The conceptual contribution is to formulate the real-world problem of preventing HTTP-based attacks on web servers as a one-shot sequential learning problem, namely as a contextual multi-armed bandit. Our second contribution is to present CMABFAS, a new algorithm for general contextual multi-armed bandit learning that specifically targets domains with finite actions. We illustrate how CMABFAS could be used to design a fully self-learning meta filter for web servers that does not rely on feedback from the end-user (i.e., does not require labeled data) and report first convincing simulation results. [less ▲]

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See detailUsing Decision Trees for Generating Adaptive SPIT Signatures
Nassar, Mohamed Ali; Martin, Sylvain ULg; Leduc, Guy ULg et al

in Proc. of the 4th International Conference on Security of Information and Networks (SIN 2011) (2011, November 14)

With the spread of new and innovative Internet services such as SIP-based communications, the challenge of protecting and defending these critical applications has been raised. In particular, SIP ... [more ▼]

With the spread of new and innovative Internet services such as SIP-based communications, the challenge of protecting and defending these critical applications has been raised. In particular, SIP firewalls attempt to filter the signaling unwanted activities and attacks based on the knowledge of the SIP protocol. Optimizing the SIP firewall configuration at real-time by selecting the best filtering rules is problematic because it depends on both natures of the legal traffic and the unwanted activities. More precisely, we do not know exactly how the unwanted activities are reflected in the SIP messages and in what they differ from the legal ones. In this paper, we address the case of Spam over Internet Telephony (SPIT) mitigation. We propose an adaptive solution based on extracting signatures from learnt decision trees. Our simulations show that quickly learning the optimal configuration for a SIP firewall leads to reduce at lowest the unsolicited calls as reported by the users under protection. Our results promote the application of machine learning algorithms for supporting network and service resilience against such new challenges. [less ▲]

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See detailA Generic Service Interface for Cloud Networks
Sifalakis, Manolis; Tschudin, Christian; Martin, Sylvain ULg et al

in Leymann, Frank; Ivanov, Ivan; van Sinderen, Marten (Eds.) CLOSER (2011, May 09)

Two major challenges for enabling the vision of cloud computing regard (a) the generic and multi-purpose access to (virtualised) resources, and (b) the flexible, dynamic, and on-demand composition of ... [more ▼]

Two major challenges for enabling the vision of cloud computing regard (a) the generic and multi-purpose access to (virtualised) resources, and (b) the flexible, dynamic, and on-demand composition of services from virtual resources; from the service level, all the way ``down'' to the lamda level. Both aspects require a respective flexibility and expressibility from the interfaces in-place, which is missing from the current static socket (and other) interfaces below the application level. In this position paper, we propose, explain and exemplify an alternative generic and universal resource interface (GRI) that borrows from object oriented design to enable properties such as polymorphic access, generic service composition, introspection and dynamic reconfigurability, of in-network resources, opening in this way the path for flexible creation of service clouds. [less ▲]

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See detailA Practical Bytecode Interpreter for Programmable Routers on Network Processor
Martin, Sylvain ULg; Leduc, Guy ULg

in Computer Networks (2009), 53(15), 2740-2751

WASP is a programmable router platform that allows end-hosts to store ephemeral state in routers along the path of IP flows and to execute packet-attached bytecode that processes this data. We exploit ... [more ▼]

WASP is a programmable router platform that allows end-hosts to store ephemeral state in routers along the path of IP flows and to execute packet-attached bytecode that processes this data. We exploit lessons from past active network research and our knowledge of network processors to design a minimal interpreter that favours language restrictions over run-time checks. WASP provides safety with limited performance penalty through predictable execution time and bounded usage of memory and network resources. WASP is expressive enough to enable several applications including statistics collection and service discovery. It can also detect common trunk of two Internet paths and exchange local measurements about these paths. We propose a robust implementation on the IXP2400 network processor, and evaluate its performance through short benchmark programs against native functions hard-coded in the router. We achieve latencies below 7$\,\mu{s}$, i.e. less than the reference IPv4 forwarding latency, and throughputs approaching 800\,kpps per core, which competes with, and sometimes even outperforms, native programs. We further exploit our results to give hints on further improving resource usage and guidelines on management of ephemeral stores in high-speed networks. [less ▲]

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See detailInterpreted Active Packets for Ephemeral State Processing Routers
Martin, Sylvain ULg; Leduc, Guy ULg

in Lecture Notes in Computer Science (2009), 4388

We propose WASP (lightweight and World-friendly Active packets for ephemeral State Processing), a new active platform based on Ephemeral State designed to allow bytecode interpretation on programmable ... [more ▼]

We propose WASP (lightweight and World-friendly Active packets for ephemeral State Processing), a new active platform based on Ephemeral State designed to allow bytecode interpretation on programmable datapath elements. We designed WASP to be a good compromise between flexibility (e.g. offering solutions in quality-adaptive multimedia flows, service discovery or mobility support) and safety (i.e. protection of router and network resource). [less ▲]

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See detailEphemeral State Assisted Discovery of Peer-to-peer Networks
Martin, Sylvain ULg; Leduc, Guy ULg

in Boutaba, Raouf; Brunner, Marcus; Schmid, Stefan (Eds.) 1st IEEE Workshop on Autonomic Communications and Network Management (2007, May)

In the past few years there has been an impressive number of proposals for application-specific overlays or peerto-peer networks. However the procedure to bootstrap peers in those networks has remained an ... [more ▼]

In the past few years there has been an impressive number of proposals for application-specific overlays or peerto-peer networks. However the procedure to bootstrap peers in those networks has remained an under-researched topic, typically left as an implementation detail. In this paper, we first study the performance of history lists, a common decentralised bootstrap mechanism used in P2P applications. We then investigate how some lightweight network support, such as Ephemeral State, could help build a P2P application that would not depend on any centralised mechanism to discover other peers. [less ▲]

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See detailAn active platform as middleware for services and communities discovery
Martin, Sylvain ULg; Leduc, Guy ULg

in Lecture Notes in Computer Science (2005, May), 3516

In an increasing number of cases, network hosts need to locate a machine based on its role in a service or community rather than based on a well-known address. We propose and evaluate WASP, a lightweight ... [more ▼]

In an increasing number of cases, network hosts need to locate a machine based on its role in a service or community rather than based on a well-known address. We propose and evaluate WASP, a lightweight active platform where ephemeral state left in the network can help locate service providers such as request dispatchers or computation aggregators. In an active grid architecture, WASP can also help locate participants, build and manage overlays. [less ▲]

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See detailLearning movement patterns in mobile networks: a generic method
François, Jean-Marc; Leduc, Guy ULg; Martin, Sylvain ULg

in European Wireless 2004 (2004, February)

Predicting terminals movements in mobile networks is useful for more than one reason, in particular for routing management. A way to do such prediction is to learn the movement patterns of mobile nodes ... [more ▼]

Predicting terminals movements in mobile networks is useful for more than one reason, in particular for routing management. A way to do such prediction is to learn the movement patterns of mobile nodes passing by an access router. In this paper, the information (e.g. layer 2 measurements) related to the different paths followed by mobiles are learned using a hidden Markov model. Simulations have been done using this method and show it can handle different layer~2 signals and collect statistical information when no such signal is available. Furthermore, the method works when no information is available and can be extended so as to guess the timing of the handoffs. [less ▲]

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See detailA dynamic neighbourhood discovery protocol for active overlay networks
Martin, Sylvain ULg; Leduc, Guy ULg

in Lecture Notes in Computer Science (2004), 2982

d-RADAR(1) is a neighbourhood discovery protocol for overlay network environments designed for (but not limited to) active network overlays. The core of the algorithm is an expanding ring-search based on ... [more ▼]

d-RADAR(1) is a neighbourhood discovery protocol for overlay network environments designed for (but not limited to) active network overlays. The core of the algorithm is an expanding ring-search based on the IP routing table content augmented with traffic-based and dynamic refreshing techniques that allows it to react to virtual topology changes (nodes joining/leaving the overlay) as well as IP topology changes (broken and repaired link, route changes and moving nodes). This paper presents how the protocol detects overlay candidate nodes using probing capsules and the algorithms needed to select neighbours among the candidates. We also show how d-RADAR keeps the neighbouring table up to date and learns topology changes while keeping a low discovery and refresh overhead. A short summary of simulations carried out with our active network simulator illustrates how these algorithms actually behave. [less ▲]

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See detailEvaluation d'une méthode de prédiction des déplacements de terminaux dans les réseaux mobiles
François, Jean-Marc; Leduc, Guy ULg; Martin, Sylvain ULg

in Ingénierie des protocoles - Réseaux mobiles et ad hoc, qualité de service, test et validation (2003, October)

Dans les réseaux mobiles, la prédiction du déplacement des terminaux fait régulièrement l'objet d'études: c'est une étape importante sur le chemin des garanties de QoS dans ces réseaux. Dans les ... [more ▼]

Dans les réseaux mobiles, la prédiction du déplacement des terminaux fait régulièrement l'objet d'études: c'est une étape importante sur le chemin des garanties de QoS dans ces réseaux. Dans les infrastructures actuelles, les sources d'informations permettant d'induire le déplacement d'un mobile sont multiples; de plus, le cas des terminaux incapables d'émettre de telles informations est aussi fréquent qu'important. Dans ces conditions, pour qu'un mécanisme de prédiction puisse se déployer, il lui faut pouvoir s'adapter à cette diversité de façon flexible. L'évaluation d'un tel mécanisme est le sujet de cet article; il s'agit d'une méthode simple et s'appuyant sur peu d'hypothèses. [less ▲]

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See detailModule de garantie de transmission
Reinbold, Pierre; Martin, Sylvain ULg; Bonaventure, Olivier et al

in ARTHUR - Manuel d'informatisation des urgences (2003)

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See detailRADAR: Ring-based adaptive discovery of active neighbour routers
Martin, Sylvain ULg; Leduc, Guy ULg

in Lecture Notes in Computer Science (2002, December), 2546

The RADAR protocol and its underlying neighbourhood discovery framework extend the ANTS toolkit by giving active nodes the ability to discover dynamically other active nodes close to them without relying ... [more ▼]

The RADAR protocol and its underlying neighbourhood discovery framework extend the ANTS toolkit by giving active nodes the ability to discover dynamically other active nodes close to them without relying on any configuration file. Such an automatic discovery is the key to administration of large or sparse active networks and the first step towards an efficient active routing. Active nodes will use their local IP routing table to run an extended ring search in their domain. An Additive Increase Multiplicative Decrease control allows RADAR to discover several neighbours per physical interface without searching too far away or fixing a maximum distance a priori. The protocol is complemented by a traffic-driven discovery that can grab capsules coming from unknown nodes (mainly outside the local domain) and trigger targetted probing of those addresses. [less ▲]

Detailed reference viewed: 51 (4 ULg)