14,559 research outputs found

    Can NSEC5 be practical for DNSSEC deployments?

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    NSEC5 is proposed modification to DNSSEC that simultaneously guarantees two security properties: (1) privacy against offline zone enumeration, and (2) integrity of zone contents, even if an adversary compromises the authoritative nameserver responsible for responding to DNS queries for the zone. This paper redesigns NSEC5 to make it both practical and performant. Our NSEC5 redesign features a new fast verifiable random function (VRF) based on elliptic curve cryptography (ECC), along with a cryptographic proof of its security. This VRF is also of independent interest, as it is being standardized by the IETF and being used by several other projects. We show how to integrate NSEC5 using our ECC-based VRF into the DNSSEC protocol, leveraging precomputation to improve performance and DNS protocol-level optimizations to shorten responses. Next, we present the first full-fledged implementation of NSEC5—extending widely-used DNS software to present a nameserver and recursive resolver that support NSEC5—and evaluate their performance under aggressive DNS query loads. Our performance results indicate that our redesigned NSEC5 can be viable even for high-throughput scenarioshttps://eprint.iacr.org/2017/099.pdfFirst author draf

    Watermarking FPGA Bitfile for Intellectual Property Protection

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    Intellectual property protection (IPP) of hardware designs is the most important requirement for many Field Programmable Gate Array (FPGA) intellectual property (IP) vendors. Digital watermarking has become an innovative technology for IPP in recent years. Existing watermarking techniques have successfully embedded watermark into IP cores. However, many of these techniques share two specific weaknesses: 1) They have extra overhead, and are likely to degrade performance of design; 2) vulnerability to removing attacks. We propose a novel watermarking technique to watermark FPGA bitfile for addressing these weaknesses. Experimental results and analysis show that the proposed technique incurs zero overhead and it is robust against removing attacks

    Improving the Watermarking Process with Usage of Block Error-Correcting Codes

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    The emergence of digital imaging and of digital networks has made duplication of original artwork easier. Watermarking techniques, also referred to as digital signature, sign images by introducing changes that are imperceptible to the human eye but easily recoverable by a computer program. Usage of error correcting codes is one of the good choices in order to correct possible errors when extracting the signature. In this paper, we present a scheme of error correction based on a combination of Reed-Solomon codes and another optimal linear code as inner code. We have investigated the strength of the noise that this scheme is steady to for a fixed capacity of the image and various lengths of the signature. Finally, we compare our results with other error correcting techniques that are used in watermarking. We have also created a computer program for image watermarking that uses the newly presented scheme for error correction

    An M-QAM Signal Modulation Recognition Algorithm in AWGN Channel

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    Computing the distinct features from input data, before the classification, is a part of complexity to the methods of Automatic Modulation Classification (AMC) which deals with modulation classification was a pattern recognition problem. Although the algorithms that focus on MultiLevel Quadrature Amplitude Modulation (M-QAM) which underneath different channel scenarios was well detailed. A search of the literature revealed indicates that few studies were done on the classification of high order M-QAM modulation schemes like128-QAM, 256-QAM, 512-QAM and1024-QAM. This work is focusing on the investigation of the powerful capability of the natural logarithmic properties and the possibility of extracting Higher-Order Cumulant's (HOC) features from input data received raw. The HOC signals were extracted under Additive White Gaussian Noise (AWGN) channel with four effective parameters which were defined to distinguished the types of modulation from the set; 4-QAM~1024-QAM. This approach makes the recognizer more intelligent and improves the success rate of classification. From simulation results, which was achieved under statistical models for noisy channels, manifest that recognized algorithm executes was recognizing in M-QAM, furthermore, most results were promising and showed that the logarithmic classifier works well over both AWGN and different fading channels, as well as it can achieve a reliable recognition rate even at a lower signal-to-noise ratio (less than zero), it can be considered as an Integrated Automatic Modulation Classification (AMC) system in order to identify high order of M-QAM signals that applied a unique logarithmic classifier, to represents higher versatility, hence it has a superior performance via all previous works in automatic modulation identification systemComment: 18 page

    Next-Generation Media: The Global Shift

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    For over a decade the Aspen Institute Communications and Society Program has convened its CEO-level Forum on Communications and Society (FOCAS) to address specific issues relating to the impact of communications media on societal institutions and values. These small, invitation-only roundtables have addressed educational, democratic, and international issues with the aim of making recommendations to policy-makers, businesses and other institutions to improve our society through policies and actions in the information and communications sectors.In the summer of 2006 the forum took a different turn. It is clear there is a revolution affecting every media business, every consumer or user of media, and every institution affected by media. In a word, everyone. FOCAS sought to define the paradigm changes underway in the media, and to identify some of the significant repercussions of those changes on society."Next Generation Media" was a three-day meeting among leaders from new media (e.g., Google, craigslist, and Second Life) and mainstream media (e.g., The New York Times and Time), from business, government, academia and the non-profit sector, all seeking a broad picture of where the digital revolution is taking us.This report of the meeting, concisely and deftly written by Richard Adler, a longtime consultant in the field, weaves insights and anecdotes from the roundtable into a coherent document supplemented with his own research and data to form an accessible, coherent treatment of this very topical subject.The specific goals of the 2006 forum were to examine the profound changes ahead for the media industries, advertisers, consumers and users in the new attention economy; to understand how the development and delivery of content are creating new business models for commercial and non-commercial media; and to assess the impact of these developments on global relations, citizenship and leadership.The report thus examines the growth of the Internet and its effect on a rapidly changing topic: the impact of new media on politics, business, society, culture, and governments the world over. The report also sheds light on how traditional media will need to adapt to face the competition of the next generation media.Beginning, as the Forum did, with data from Jeff Cole's Center for the Digital Future at the University of Southern California, Adler documents the increasing popularity of the Internet for information, entertainment and communication. Users are increasingly generating and contributing content to the web and connecting to social networks. They are posting comments, uploading pictures, sharing videos, blogging and vlogging, chatting through instant messages or voice over Internet (VoIP), or emailing friends, business colleagues, neighbors and even strangers. As Cole observes, "Traditional media informed people but didn't empower them." New media do.The report describes three of the Internet's most successful ventures -- Wikipedia, Second Life, and craigslist. Wikipedia is a prime example of how an Internet platform allows its users to generate content and consume it. As a result of "wiki" software technology anyone can contribute or edit existing information free of cost. Second Life, a virtual world, sells virtual real estate where subscribers, in avatar form, can conduct conversations, go to lectures, even create a business. Craigslist, a predominantly free online classified site with listings in every major city in the United States, has become so popular that it is posing a significant threat to newspapers as it competes with their classified ad revenues.As a result of these and other new media phenomena, not the least being Google and Yahoo, print publications are wrestling with new business models that could entail fundamentally restructuring the way they operate. For instance, reporters are now expected to report a story on multiple media platforms and discuss them online with readers. Newspaper publisher Gannett is exploring the incorporation of usergenerated news or "citizen-journalism" into its news pages.In an era of abundant choices marketers have an even greater challenge to figure out how best to appeal to consumers. The report explores how marketers, e.g., of Hollywood movies or pomegranate juice, are moving from traditional or mainstream media to viral and other marketing techniques.For much of the world, the mobile phone rather than the computer is the most important communications device. Users depend on their phones to send and receive messages, pictures, and download information rather than just talk. In developing countries mobile phones are having an exceptional impact, penetrating regions which are not being serviced by land lines. Thus we are seeing new uses daily for this increased connectivity, from reporting election results in emerging democracies to opposing authoritarian governments in order to bring about new democracies.Meanwhile, the report discusses the need for the United States to develop a new form of public diplomacy rather than the traditional top-down approach to communicating to foreign citizens. This topic has been a recurring theme at FOCAS conferences the past few years, this year calling for more citizen diplomacy -- that is, more person-toperson contact across borders through uses of the new media. Indeed, Peter Hirshberg suggested that American leaders should listen more to the outside world to effectively manage what he called "Brand America."Finally, after acknowledging the detrimental effects that new technologies can bring about, the report discusses what role those technologies could play in expanding freedom and opportunity for the next generation. As a conclusion, FOCAS co-chair Marc Nathanson proposed adding a ninth goal to the United Nations Millennium Goals, namely, "to provide access to appropriate new technologies.
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