21,710 research outputs found

    Adaptively Secure Computationally Efficient Searchable Symmetric Encryption

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    Searchable encryption is a technique that allows a client to store documents on a server in encrypted form. Stored documents can be retrieved selectively while revealing as little information as\ud possible to the server. In the symmetric searchable encryption domain, the storage and the retrieval are performed by the same client. Most conventional searchable encryption schemes suffer\ud from two disadvantages.\ud First, searching the stored documents takes time linear in the size of the database, and/or uses heavy arithmetic operations.\ud Secondly, the existing schemes do not consider adaptive attackers;\ud a search-query will reveal information even about documents stored\ud in the future. If they do consider this, it is at a significant\ud cost to updates.\ud In this paper we propose a novel symmetric searchable encryption\ud scheme that offers searching at constant time in the number of\ud unique keywords stored on the server. We present two variants of\ud the basic scheme which differ in the efficiency of search and\ud update. We show how each scheme could be used in a personal health\ud record system

    Finding What You Need, and Knowing What You Can Find: Digital Tools for Palaeographers in Musicology and Beyond

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    This chapter examines three projects that provide musicologists with a range of resources for managing and exploring their materials: DIAMM (Digital Image Archive of Medieval Music), CMME (Computerized Mensural Music Editing) and the software Gamera. Since 1998, DIAMM has been enhancing research of scholars worldwide by providing them with the best possible quality of digital images. In some cases these images are now the only access that scholars are permitted, since the original documents are lost or considered too fragile for further handling. For many sources, however, simply creating a very high-resolution image is not enough: sources are often damaged by age, misuse (usually Medieval ‘vandalism’), or poor conservation. To deal with damaged materials the project has developed methods of digital restoration using mainstream commercial software, which has revealed lost data in a wide variety of sources. The project also uses light sources ranging from ultraviolet to infrared in order to obtain better readings of erasures or material lost by heat or water damage. The ethics of digital restoration are discussed, as well as the concerns of the document holders. CMME and a database of musical sources and editions, provides scholars with a tool for making fluid editions and diplomatic transcriptions: without the need for a single fixed visual form on a printed page, a computerized edition system can utilize one editor’s transcription to create any number of visual forms and variant versions. Gamera, a toolkit for building document image recognition systems created by Ichiro Fujinaga is a broad recognition engine that grew out of music recognition, which can be adapted and developed to perform a number of tasks on both music and non-musical materials. Its application to several projects is discussed

    Towards an Information Theoretic Analysis of Searchable Encryption (Extended Version)

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    Searchable encryption is a technique that allows a client to store data in encrypted form on a curious server, such that data can be retrieved while leaking a minimal amount of information to the server. Many searchable encryption schemes have been proposed and proved secure in their own computational model. In this paper we propose a generic model for the analysis of searchable encryptions. We then identify the security parameters of searchable encryption schemes and prove information theoretical bounds on the security of the parameters. We argue that perfectly secure searchable encryption schemes cannot be efficient. We classify the seminal schemes in two categories: the schemes that leak information upfront during the storage phase, and schemes that leak some information at every search. This helps designers to choose the right scheme for an application

    The Invisible Web: A Quick Overview

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    This article provides a quick overview of recent literature published about the Invisible Web. In particular, this article covers such topics as what is the Invisible Web, weaknesses of popular search engines, types of information found on the Invisible Web, when to use the Invisible Web, search tools and search strategies

    Forward Private Searchable Symmetric Encryption with Optimized I/O Efficiency

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    Recently, several practical attacks raised serious concerns over the security of searchable encryption. The attacks have brought emphasis on forward privacy, which is the key concept behind solutions to the adaptive leakage-exploiting attacks, and will very likely to become mandatory in the design of new searchable encryption schemes. For a long time, forward privacy implies inefficiency and thus most existing searchable encryption schemes do not support it. Very recently, Bost (CCS 2016) showed that forward privacy can be obtained without inducing a large communication overhead. However, Bost's scheme is constructed with a relatively inefficient public key cryptographic primitive, and has a poor I/O performance. Both of the deficiencies significantly hinder the practical efficiency of the scheme, and prevent it from scaling to large data settings. To address the problems, we first present FAST, which achieves forward privacy and the same communication efficiency as Bost's scheme, but uses only symmetric cryptographic primitives. We then present FASTIO, which retains all good properties of FAST, and further improves I/O efficiency. We implemented the two schemes and compared their performance with Bost's scheme. The experiment results show that both our schemes are highly efficient, and FASTIO achieves a much better scalability due to its optimized I/O

    The Development and Usage of the Greenstone Digital Library Software

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    The Greenstone software has helped spread the practical impact of digital library technology throughout the world-particularly in developing countries. This article reviews the project’s origins, usage, and the development of support mechanisms for Greenstone users. We begin with a brief summary of salient aspects of this open source software package and its user population. Next we describe how its international, humanitarian focus arose. We then review the special requirements imposed by the conditions that prevail in developing courtiers. Finally we discuss efforts to establish regional support organizations for Greenstone in India and Africa

    Review of Paradox and Platitude in Wittgenstein's Philosophy by David Pears (2006)(review revised 2019)

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    Pears is an eminent philosopher, notable among W scholars for his “The False Prison: a study of the development of Wittgenstein’s philosophy” in 2 volumes published 20 years ago. Based on these facts I expected some deep insights into W in the current volume. There were certainly some good points but overall it was profoundly disappointing. All of behavioral science is about our innate human nature and since W was the first to elucidate the axioms of our universal psychology, I expected this to be front and center in a work written during the golden age of evolutionary and cognitive psychology and with much good recent work on W appearing. However, one would never guess from this book that W or philosophy had any connection with psychology or indeed that there is such a thing as evolutionary psychology. Hence, I cannot recommend Pears works and instead provide a framework for rationality totally lacking in Pears (and most writing on human behavior). Those wishing a comprehensive up to date framework for human behavior from the modern two systems view may consult my book ‘The Logical Structure of Philosophy, Psychology, Mind and Language in Ludwig Wittgenstein and John Searle’ 2nd ed (2019). Those interested in more of my writings may see ‘Talking Monkeys--Philosophy, Psychology, Science, Religion and Politics on a Doomed Planet--Articles and Reviews 2006-2019 3rd ed (2019), The Logical Structure of Human Behavior (2019), and Suicidal Utopian Delusions in the 21st Century 4th ed (2019
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