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arXiv · 1604.02533

Joint Data Purchasing and Data Placement in a Geo-Distributed Data Market

Abstract

This paper studies two design tasks faced by a geo-distributed cloud data market: which data to purchase (data purchasing) and where to place/replicate the data for delivery (data placement). We show that the joint problem of data purchasing and data placement within a cloud data market can be viewed as a facility location problem, and is thus NP-hard. However, we give a provably optimal algorithm for the case of a data market made up of a single data center, and then generalize the structure from the single data center setting in order to develop a near-optimal, polynomial-time algorithm for a geo-distributed data market. The resulting design, Datum, decomposes the joint purchasing and placement problem into two subproblems, one for data purchasing and one for data placement, using a transformation of the underlying bandwidth costs. We show, via a case study, that Datum is near-optimal (within 1.6%) in practical settings.

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Xiaoqi Ren, Palma London, Juba Ziani, Adam Wierman. 2016-04-09. Joint Data Purchasing and Data Placement in a Geo-Distributed Data Market. https://arxiv.org/abs/1604.02533

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