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.

Data Analytics Service Composition and Deployment on Edge Devices

Abstract: Data analytics on edge devices has gained rapid growth in research, industry, and different aspects of our daily life. This topic still faces many challenges such as limited computation resource on edge devices. In this paper, we further identify two main challenges: the composition and deployment of data analytics services on edge devices. We present the Zoo system to address these two challenge: on one hand, it provides simple and concise domain-specific language to enable easy and and type-safe composition of different data analytics services; on the other, it utilises multiple deployment backends, including Docker container, JavaScript, and MirageOS, to accommodate the heterogeneous edge deployment environment. We show the expressiveness of Zoo with a use case, and thoroughly compare the performance of different deployment backends in evaluation.

On the duality of resilience and privacy

Abstract: Protecting information has long been an important problem We would like to protect ourselves from the risk of loss: think of the library of Alexandria; and from unauthorized access: consider the very business of the 'Scandal Sheets', going back centuries This has never been more true than today when vast quantities of data (dare one say lesser quantities of information) are stored on computer systems, and routinely moved around the Internet, at almost no cost Computer and communication systems are both fragile and vulnerable, and so the risk of catastrophic loss or theft is potentially much higher A single keystroke can delete a public database, or expose a private dataset to the world In this paper, I consider the problems of providing resilience against loss, and against unacceptable access as a dual Here, we see that two apparently different solutions to different technical problems may be transformed into one another, and hence give better insight into both problems

Multimedia teleconferencing over international packet switched networks

Abstract: A description is presented of the current configuration and projected future work on the world's first multimedia teleconferencing system. The communications architecture (by which the authors refer to the protocols and supporting network management system) is based around the DARPA Internet Protocol suite, but with certain enhancements to support real time traffic. The CODEC runs a standard bitstream encoding of video, and this is packetized by the PC. However, this is not sufficiently flexible a protocol to traverse the Internet. The stream protocol (ST) gateway then runs two further protocols to carry the video and voice: (1) packet video protocol (PVP) and (2) voice traffic protocol (VT). Each of these is tuned to the special requirements of video and voice. To carry these in a reasonably consistent fashion, the gateways then run the ST. The performance of the system is limited mainly by the bandwidth of the first few hops of the path. >

How to Enable Policy-Based Interactions in Dynamic Wireless Networks?

Abstract: Policy is a key component in the interoperations among multiple heterogeneous domains of networks with different routing metrics and preferences. IDRM is a recent protocol that enables policy-based inter-domain routing over mobile ad hoc networks (MANETs), supporting dynamic network topology and diverse intra-domain routing protocols. Notwithstanding a protocol to interoperate multi- domain MANETs, there are fundamental challenges to support dynamic networks - how can network administrators formulate practical inter-domain routing policies considering MANET-specific characteristics. This paper studies this issue with illustrating examples, and discusses potential solutions.

I and i

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 …

Community detection in graphs

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.