Well Balanced Designs for Data Placement
نویسندگان
چکیده
The problem we consider in this article is motivated by data placement in particular data replication in video on demand systems. We are given a set V of n servers and b files (data, documents). Each file is replicated on exactly k servers. The problem is to determine the placement that minimizes the variance of the number of unavailable datas. To do that, we consider the problem of determining well balanced designs, a difficult problem because it contains the problem of the existence of Steiner systems. Key-words: data placement, balanced designs, Steiner systems This work was partially funded by Région PACA. ∗ MASCOTTE, INRIA, I3S, CNRS, Univ. Nice Sophia, Sophia Antipolis, France. [email protected] in ria -0 06 18 65 6, v er si on 2 5 Se p 20 11 Configurations bien équilibrées pour le placement de données dans les réseaux pair-à-pair Résumé : Nous considérons un problème motivé par la réplication des données dans un système de vidéo à la demande [BBJMR09b, JMRBB09] où chaque donnée est répliquée sur exactement k serveurs et où chaque serveur peut tomber en panne. Nous cherchons à déterminer un placement minimisant la variance du nombre de données indisponibles. Nous ramenons ce problème à un problème d’existence de configurations “équilibrées”, problème difficile car il contient le problème de l’existence de système de Steiner. Mots-clés : placement de données, configurations équilibres, systèmes de Steiner in ria -0 06 18 65 6, v er si on 2 5 Se p 20 11 Well Balanced Designs for Data Placement 3
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