Philippe Pucheral

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Databases are hosted by a growing number of lightweight intelligent devices like palmtops, cellular phones, car computers and even smart cards. Mobility and disconnected computing are two major issues in such environment. This paper deals with the way databases can be exploited in this context while maintaining a strong transactional coherency. More(More)
Smartcards are the most secure portable computing device today. They have been used successfully in applications involving money, and proprietary and personal data (such as banking, healthcare, insurance, etc.). As smartcards get more powerful (with 32-bit CPU and more than 1 MB of stable memory in the next versions) and become multi-application, the need(More)
The erosion of trust put in traditional database servers and in Database Service Providers, the growing interest for different forms of data dissemination and the concern for protecting children from suspicious Internet content are different factors that lead to move the access control from servers to clients. Several encryption schemes can be used to serve(More)
The democratization of ubiquitous computing (access data anywhere, anytime, anyhow), the increasing connection of corporate databases to the Internet and the today’s natural resort to Webhosting companies strongly emphasize the need for data confidentiality. Database servers arouse user’s suspicion because no one can fully trust traditional security(More)
NAND Flash has become the most popular stable storage medium for embedded systems. As on-board storage capacity increases, the need for efficient indexing techniques arises. Such techniques are very challenging to design due to a combination of NAND Flash constraints (for example the block-erase-before-page-rewrite constraint and limited number of erase(More)
Pervasive computing introduces data management requirements that must be tackled in a growing variety of lightweight computing devices. Personal folders on chip, networks of sensors and data hosted by autonomous mobile computers are different illustrations of the need for evaluating queries confined in hardware constrained computing devices. RAM is the most(More)
Imagine that you have been entrusted with private data, such as corporate product information, sensitive government information, or symptom and treatment information about hospital patients. You may want to issue queries whose result will combine private and public data, but private data must not be revealed. GhostDB is an architecture and system to achieve(More)
With the emergence of XML as the de facto standard to exchange and disseminate information, the problem of regulating access to XML documents has attracted a considerable attention in recent years. Existing models attach authorizations to nodes of an XML document but disregard relationships between them. However, ancestor and sibling relationships may(More)