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Author

Jon Crowcroft

Bio: Jon Crowcroft is an academic researcher from University of Cambridge. The author has contributed to research in topics: The Internet & Multicast. The author has an hindex of 87, co-authored 672 publications receiving 38848 citations. Previous affiliations of Jon Crowcroft include Memorial University of Newfoundland & Information Technology University.


Papers
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Proceedings ArticleDOI
01 Sep 2018
TL;DR: This poster presents results establishing the effectiveness of Kiram based on substantial simulations over a fairly realistic topology and proposes Kiram as an intelligent anomaly recognition and alert generation mechanism serving as a collaborative countermeasure to a DDoS attack.
Abstract: The current Internet infrastructure, initially conceived to provide closed group connectivity to a limited user-base, is now facing the challenges of catering to over three billion users with dynamically changing data, transport, and access requirements. Content-Centric Networking (CCN) is being explored as a possible future Internet architecture. Named-Data Networking (NDN) exemplifies CCN and with the ever-changing security landscape, it is imperative to build it with intrinsic resilience based on the security by design narrative. In this extended abstract, we explore the fake interest fiooding by adversaries to launch a Distributed Denial of Service (DDoS) attack in NDN. We propose Kiram as an intelligent anomaly recognition and alert generation mechanism serving as a collaborative countermeasure to a DDoS attack. The alert generated by Kiram is named Warding Off Evil (WOE). This poster presents results establishing the effectiveness of Kiram based on substantial simulations over a fairly realistic topology.

1 citations

01 Sep 1998
TL;DR: The work described is a series of separate efforts to add protocols to NS, and the design effort to enhance NS to provide interworking between real and simulated (actual and virtual) systems.
Abstract: This note is about some of the technical work that UCL CS people have done, partly Jon at HP's Internet Research Institute during the first quarter of 1998, but also previous work using NS under several projects, notably MERCI, HIPAPRCH and DARPA work. The work described is a series of separate efforts to add protocols to NS, and the design effort to enhance NS to provide interworking between real and simulated (actual and virtual) systems.

1 citations

Journal ArticleDOI
09 Aug 2021
TL;DR: This work provides a closed‐form expression for the EC of relay‐assisted D2D communication, in which both the transmitter and the relay devices operate under individual QoS constraints, and proposes a novel multiple features‐based mechanism by utilizing all the features of a wireless link.
Abstract: Device‐to‐device (D2D) communication is a promising technique to enhance the spectral efficiency for 5G and beyond cellular networks. Traditionally, D2D communication was considered solely...

1 citations

Posted Content
TL;DR: An immunity system with Phagocytes --- a small subset of elected P2P hosts that are immune with high probability and specialized in finding and "eating" worms in the P1P overlay to restrain external worms attacking the P3P overlay, without influencing legitimate hosts' experiences significantly.
Abstract: Active Peer-to-Peer (P2P) worms present serious threats to the global Internet by exploiting popular P2P applications to perform rapid topological self-propagation. Active P2P worms pose more deadly threats than normal scanning worms because they do not exhibit easily detectable anomalies, thus many existing defenses are no longer effective. We propose an immunity system with Phagocytes --- a small subset of elected P2P hosts that are immune with high probability and specialized in finding and "eating" worms in the P2P overlay. The Phagocytes will monitor their managed P2P hosts' connection patterns and traffic volume in an attempt to detect active P2P worm attacks. Once detected, local isolation, alert propagation and software patching will take place for containment. The Phagocytes further provide the access control and filtering mechanisms for communication establishment between the internal P2P overlay and the external hosts. We design a novel adaptive and interaction-based computational puzzle scheme at the Phagocytes to restrain external worms attacking the P2P overlay, without influencing legitimate hosts' experiences significantly. We implement a prototype system, and evaluate its performance based on realistic massive-scale P2P network traces. The evaluation results illustrate that our Phagocytes are capable of achieving a total defense against active P2P worms.

1 citations


Cited by
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Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: In this paper, Imagined communities: Reflections on the origin and spread of nationalism are discussed. And the history of European ideas: Vol. 21, No. 5, pp. 721-722.

13,842 citations

Journal ArticleDOI
TL;DR: A thorough exposition of community structure, or clustering, is attempted, from the definition of the main elements of the problem, to the presentation of most methods developed, with a special focus on techniques designed by statistical physicists.
Abstract: The modern science of networks has brought significant advances to our understanding of complex systems. One of the most relevant features of graphs representing real systems is community structure, or clustering, i. e. the organization of vertices in clusters, with many edges joining vertices of the same cluster and comparatively few edges joining vertices of different clusters. Such clusters, or communities, can be considered as fairly independent compartments of a graph, playing a similar role like, e. g., the tissues or the organs in the human body. Detecting communities is of great importance in sociology, biology and computer science, disciplines where systems are often represented as graphs. This problem is very hard and not yet satisfactorily solved, despite the huge effort of a large interdisciplinary community of scientists working on it over the past few years. We will attempt a thorough exposition of the topic, from the definition of the main elements of the problem, to the presentation of most methods developed, with a special focus on techniques designed by statistical physicists, from the discussion of crucial issues like the significance of clustering and how methods should be tested and compared against each other, to the description of applications to real networks.

9,057 citations

Journal ArticleDOI
TL;DR: A thorough exposition of the main elements of the clustering problem can be found in this paper, with a special focus on techniques designed by statistical physicists, from the discussion of crucial issues like the significance of clustering and how methods should be tested and compared against each other, to the description of applications to real networks.

8,432 citations