Arturo Crespo

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In a peer-to-peer (P2P) system, nodes typically connect to a small set of random nodes (their neighbors), and queries are propagated along these connections. Such query flooding tends to be very expensive. We propose that node connections be influenced by content, so that for example, nodes having many “Jazz” files will connect to other similar nodes. Thus,(More)
This paper introduces techniques for reducing data dissemination costs of query subscriptions in a multicast environment. The reduction is achieved by merging queries with overlapping, but not necessarily equal, answers. The paper formalizes the query-merging problem and introduces a general framework and cost model for evaluating merging. We prove that the(More)
Peer-to-peer (P2P) systems have become a popular medium through which to share huge amounts of data. P2P systems distribute the main costs of sharing data – disk space for storing files and bandwidth for transferring them across the peers in the network, thus enabling applications to scale without the need for powerful, expensive servers. Their ability to(More)
We propose an architecture for Digital Library Repositories that assures long-term archival storage of digital objects. The architecture is formed by a federation of independent but collaborating sites, each managing a collection of digital objects. The architecture is based on the following key components: use of signatures as object handles, no deletions(More)
Constructing server-based Web applications requires creating both Web pages and programs that generate Web pages. This requires a knowledge of the Hypertext Markup Language (HTML), the Common Gateway Interface (CGI) protocol, and a programming language, such as C++, Python, or Perl. While this is not a barrier for programmers, it is for non-programmers.(More)