28 research outputs found

    Econometric Feedback for Runtime Risk Management in VoIP Architectures

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    Part 1: Security ManagementInternational audienceVoIP infrastructures are exposed to a large variety of security attacks, but the deployment of security safeguards may deteriorate their performance. Risk management provides new perspectives for addressing this issue. Risk models permit to reduce these attacks while maintaining the quality of such a critical service. These models often suïŹ€er from their complexity due to the high number of parameters to be conïŹgured. We therefore propose in this paper a self-conïŹguration strategy for support- ing runtime risk management in VoIP architectures. This strategy aims at automatically adapting these parameters based on an econometric feedback mechanism. We mathematically describe this self-conïŹguration strategy, show how it can be integrated into our runtime risk model. We then evaluate its deployment based on a proof-of-concept prototype, and quantify its performance through an extensive set of simulation results

    Experimentation and Characterization of Mobile Broadband Networks

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    The Internet has brought substantial changes to our life as the main tool to access a large variety of services and applications. Internet distributed nature and technological improvements lead to new challenges for researchers, service providers, and network administrators. Internet traffic measurement and analysis is one of the most trivial and powerful tools to study such a complex environment from different aspects. Mobile BroadBand (MBB) networks have become one of the main means to access the Internet. MBB networks are evolving at a rapid pace with technology enhancements that promise drastic improvements in capacity, connectivity, and coverage, i.e., better performance in general. Open experimentation with operational MBB networks in the wild is currently a fundamental requirement of the research community in its endeavor to address the need for innovative solutions for mobile communications. There is a strong need for objective data relating to stability and performance of MBB (e.g., 2G, 3G, 4G, and soon-to-come 5G) networks and for tools that rigorously and scientifically assess their performance. Thus, measuring end user performance in such an environment is a challenge that calls for large-scale measurements and profound analysis of the collected data. The intertwining of technologies, protocols, and setups makes it even more complicated to design scientifically sound and robust measurement campaigns. In such a complex scenario, the randomness of the wireless access channel coupled with the often unknown operator configurations makes this scenario even more challenging. In this thesis, we introduce the MONROE measurement platform: an open access and flexible hardware-based platform for measurements on operational MBB networks. The MONROE platform enables accurate, realistic, and meaningful assessment of the performance and reliability of MBB networks. We detail the challenges we overcame while building and testing the MONROE testbed and argue our design and implementation choices accordingly. Measurements are designed to stress performance of MBB networks at different network layers by proposing scalable experiments and methodologies. We study: (i) Network layer performance, characterizing and possibly estimating the download speed offered by commercial MBB networks; (ii) End users’ Quality of Experience (QoE), specifically targeting the web performance of HTTP1.1/TLS and HTTP2 on various popular web sites; (iii) Implication of roaming in Europe, understanding the roaming ecosystem in Europe after the "Roam like Home" initiative; and (iv) A novel adaptive scheduler family with deadline is proposed for multihomed devices that only require a very coarse knowledge of the wireless bandwidth. Our results comprise different contributions in the scope of each research topic. To put it in a nutshell, we pinpoint the impact of different network configurations that further complicate the picture and hopefully contribute to the debate about performance assessment in MBB networks. The MBB users web performance shows that HTTP1.1/TLS is very similar to HTTP2 in our large-scale measurements. Furthermore, we observe that roaming is well supported for the monitored operators and the operators using the same approach for routing roaming traffic. The proposed adaptive schedulers for content upload in multihomed devices are evaluated in both numerical simulations and real mobile nodes. Simulation results show that the adaptive solutions can effectively leverage the fundamental tradeoff between the upload cost and completion time, despite unpredictable variations in available bandwidth of wireless interfaces. Experiments in the real mobile nodes provided by the MONROE platform confirm the findings

    The emergence of the mobile internet in Japan and the UK: platforms, exchange models, and innovation 1999‐2011

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    In 1999 Japanese mobile operator NTT DoCoMo launched arguably the world’s first successful mobile Internet services portal called “i‐mode”. In Europe at the same time a series of failures diminished the opportunities to attract customers to the mobile Internet. Even though similar Internet technologies were available in Japan and the UK, very different markets for services developed during the initial years 1999‐2003. When the West expected Japanese firms to become dominant players in the mobile digitalisation of services during the introduction of 3G networks, it remained instead a national affair. The dominant views of how markets for mobile services operated seemed flawed.   So‐called delivery platforms were used to connect mobile phones with service contents that were often adapted from the PC world. Designing and operating service delivery platforms became a new niche market. It held a pivotal role for the output of services and competition among providers.   This thesis sets out to answer a set of inter‐related questions: How and where did firms innovate in this new and growing part of the service economy and how are new business models mediated by service delivery platforms? It argues that innovation in the digitalised economy is largely influenced by firms achieving platform leadership through coordination of both technological systems and the creation of multi‐sided exchanges. This thesis demonstrates from cases of multi‐sided markets in operator‐controlled portals, of mobile video and TV and of event ticketing in Japan and the UK that defining the scope of the firm on the network level forms the basis for incremental innovation, the dominant form of service innovation. A parallel focus on coordinating platform technology choices forms the basis for firms to trade fees, advertisements, and user data, enabling control over profitable parts of multi‐sided value networks

    Information technology and military performance

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Political Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 519-544).Militaries have long been eager to adopt the latest technology (IT) in a quest to improve knowledge of and control over the battlefield. At the same time, uncertainty and confusion have remained prominent in actual experience of war. IT usage sometimes improves knowledge, but it sometimes contributes to tactical blunders and misplaced hubris. As militaries invest intensively in IT, they also tend to develop larger headquarters staffs, depend more heavily on planning and intelligence, and employ a larger percentage of personnel in knowledge work rather than physical combat. Both optimists and pessimists about the so-called "revolution in military affairs" have tended to overlook the ways in which IT is profoundly and ambiguously embedded in everyday organizational life. Technocrats embrace IT to "lift the fog of war," but IT often becomes a source of breakdowns, misperception, and politicization. To describe the conditions under which IT usage improves or degrades organizational performance, this dissertation develops the notion of information friction, an aggregate measure of the intensity of organizational struggle to coordinate IT with the operational environment. It articulates hypotheses about how the structure of the external battlefield, internal bureaucratic politics, and patterns of human-computer interaction can either exacerbate or relieve friction, which thus degrades or improves performance. Technological determinism alone cannot account for the increasing complexity and variable performances of information phenomena. Information friction theory is empirically grounded in a participant-observation study of U.S. special operations in Iraq from 2007 to 2008. To test the external validity of insights gained through fieldwork in Iraq, an historical study of the 1940 Battle of Britain examines IT usage in a totally different structural, organizational, and technological context.(cont.) These paired cases show that high information friction, and thus degraded performance, can arise with sophisticated IT, while lower friction and impressive performance can occur with far less sophisticated networks. The social context, not just the quality of technology, makes all the difference. Many shorter examples from recent military history are included to illustrate concepts. This project should be of broad interest to students of organizational knowledge, IT, and military effectiveness.by Jon Randall Lindsay.Ph.D

    CHORUS Deliverable 2.1: State of the Art on Multimedia Search Engines

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    Based on the information provided by European projects and national initiatives related to multimedia search as well as domains experts that participated in the CHORUS Think-thanks and workshops, this document reports on the state of the art related to multimedia content search from, a technical, and socio-economic perspective. The technical perspective includes an up to date view on content based indexing and retrieval technologies, multimedia search in the context of mobile devices and peer-to-peer networks, and an overview of current evaluation and benchmark inititiatives to measure the performance of multimedia search engines. From a socio-economic perspective we inventorize the impact and legal consequences of these technical advances and point out future directions of research

    Information Management and Market Engineering. Vol. II

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    The research program Information Management and Market Engineering focuses on the analysis and the design of electronic markets. Taking a holistic view of the conceptualization and realization of solutions, the research integrates the disciplines business administration, economics, computer science, and law. Topics of interest range from the implementation, quality assurance, and advancement of electronic markets to their integration into business processes and legal frameworks

    Semantic discovery and reuse of business process patterns

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    Patterns currently play an important role in modern information systems (IS) development and their use has mainly been restricted to the design and implementation phases of the development lifecycle. Given the increasing significance of business modelling in IS development, patterns have the potential of providing a viable solution for promoting reusability of recurrent generalized models in the very early stages of development. As a statement of research-in-progress this paper focuses on business process patterns and proposes an initial methodological framework for the discovery and reuse of business process patterns within the IS development lifecycle. The framework borrows ideas from the domain engineering literature and proposes the use of semantics to drive both the discovery of patterns as well as their reuse

    Wireless networks for the developing world

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    Thesis (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2004.Includes bibliographical references (p. 216-226).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.As radio technologies and public policies evolve, an increasing amount of spectrum is being set aside for transmission use without a license. These license-exempt, or "unlicensed" bands, include 2.4 GHz and 5 GHz in the USA and much of Europe. I argue that this unlicensed spectrum, and low-cost wireless technologies that operate in these bands, is of particular value in the developing world, where it has the potential to substantially impact accessibility and availability of information and telecommunication services. In the context of numerous institutional and structural obstacles to entry license-exempt regulation potentially provides a friendly environment for entrepreneurship, reducing barriers to entry and the risk of regulatory capture. In order to assess this opportunity in the context of Africa, I have surveyed every country in the continent on their regulations and use of the 2.4 and 5 GHz bands. Responses, from differing country informants though mostly from the regulators themselves, were received from 47 of the 54 countries of Africa, which accounts for 95% of the continent's population. The responses show that there is significant diversity and heterogeneity in the regulation of these bands across Africa. Not only do licensing requirements and specific conditions change widely from country to country, but so do power, range and services restrictions, as well as certification requirements. In addition, regulation is still not in place in some countries, and is changing in others. Enforcement is low, adding to overall uncertainty. Lack of clarity in regulation and enforcement creates confusion and may discourage smaller players from entering the market. For bigger players interested in taking advantage of economies of scale(cont.) and implementing common strategies across borders, the heterogeneous regulatory environment will also act as a deterrent and a barrier to entry. Despite this heterogeneity, these bands are being used in most African countries, not only for "hotspot" style or other localized coverage in urban areas, but also for longer area coverage. A significant 37% of the countries that responded are using wireless technologies operating in these bands for providing backhaul network connectivity in rural areas. In unlicensed bands regulation tends to place a burden on the transmitter though, e.g. through power restrictions, in particular where competition in the market is low. In view of the continent's weak teledensity and lack of alternative infrastructure, establishing a more certain and uniform regulatory framework and promoting an appropriate business climate across Africa may be instrumental in encouraging private investment and connectivity through technology in these bands. The TU may have a key role to play, both by issuing clearer guidelines for the regulation of license-exempt bands, and by serving as a convening forum for countries to establish common regulatory strategies. While a fair balance is needed in regulation, this thesis argues that governments should err on the side of laxity in order to lower barriers to entry and counterbalance current overregulation of these bands.by Maria Isabel A.S. Neto.S.M

    Proceedings der 11. Internationalen Tagung Wirtschaftsinformatik (WI2013) - Band 1

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    The two volumes represent the proceedings of the 11th International Conference on Wirtschaftsinformatik WI2013 (Business Information Systems). They include 118 papers from ten research tracks, a general track and the Student Consortium. The selection of all submissions was subject to a double blind procedure with three reviews for each paper and an overall acceptance rate of 25 percent. The WI2013 was organized at the University of Leipzig between February 27th and March 1st, 2013 and followed the main themes Innovation, Integration and Individualization.:Track 1: Individualization and Consumerization Track 2: Integrated Systems in Manufacturing Industries Track 3: Integrated Systems in Service Industries Track 4: Innovations and Business Models Track 5: Information and Knowledge ManagementDie zweibĂ€ndigen TagungsbĂ€nde zur 11. Internationalen Tagung Wirtschaftsinformatik (WI2013) enthalten 118 ForschungsbeitrĂ€ge aus zehn thematischen Tracks der Wirtschaftsinformatik, einem General Track sowie einem Student Consortium. Die Selektion der Artikel erfolgte nach einem Double-Blind-Verfahren mit jeweils drei Gutachten und fĂŒhrte zu einer Annahmequote von 25%. Die WI2013 hat vom 27.02. - 01.03.2013 unter den Leitthemen Innovation, Integration und Individualisierung an der UniversitĂ€t Leipzig stattgefunden.:Track 1: Individualization and Consumerization Track 2: Integrated Systems in Manufacturing Industries Track 3: Integrated Systems in Service Industries Track 4: Innovations and Business Models Track 5: Information and Knowledge Managemen

    Challenges in Cybersecurity and Privacy - the European Research Landscape

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    Cybersecurity and Privacy issues are becoming an important barrier for a trusted and dependable global digital society development. Cyber-criminals are continuously shifting their cyber-attacks specially against cyber-physical systems and IoT, since they present additional vulnerabilities due to their constrained capabilities, their unattended nature and the usage of potential untrustworthiness components. Likewise, identity-theft, fraud, personal data leakages, and other related cyber-crimes are continuously evolving, causing important damages and privacy problems for European citizens in both virtual and physical scenarios. In this context, new holistic approaches, methodologies, techniques and tools are needed to cope with those issues, and mitigate cyberattacks, by employing novel cyber-situational awareness frameworks, risk analysis and modeling, threat intelligent systems, cyber-threat information sharing methods, advanced big-data analysis techniques as well as exploiting the benefits from latest technologies such as SDN/NFV and Cloud systems. In addition, novel privacy-preserving techniques, and crypto-privacy mechanisms, identity and eID management systems, trust services, and recommendations are needed to protect citizens’ privacy while keeping usability levels. The European Commission is addressing the challenge through different means, including the Horizon 2020 Research and Innovation program, thereby financing innovative projects that can cope with the increasing cyberthreat landscape. This book introduces several cybersecurity and privacy research challenges and how they are being addressed in the scope of 15 European research projects. Each chapter is dedicated to a different funded European Research project, which aims to cope with digital security and privacy aspects, risks, threats and cybersecurity issues from a different perspective. Each chapter includes the project’s overviews and objectives, the particular challenges they are covering, research achievements on security and privacy, as well as the techniques, outcomes, and evaluations accomplished in the scope of the EU project. The book is the result of a collaborative effort among relative ongoing European Research projects in the field of privacy and security as well as related cybersecurity fields, and it is intended to explain how these projects meet the main cybersecurity and privacy challenges faced in Europe. Namely, the EU projects analyzed in the book are: ANASTACIA, SAINT, YAKSHA, FORTIKA, CYBECO, SISSDEN, CIPSEC, CS-AWARE. RED-Alert, Truessec.eu. ARIES, LIGHTest, CREDENTIAL, FutureTrust, LEPS. Challenges in Cybersecurity and Privacy - the European Research Landscape is ideal for personnel in computer/communication industries as well as academic staff and master/research students in computer science and communications networks interested in learning about cyber-security and privacy aspects
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