Title
Distributed storage allocations for optimal delay
Abstract
We examine the problem of creating an encoded distributed storage representation of a data object for a network of mobile storage nodes so as to achieve the optimal recovery delay. A source node creates a single data object and disseminates an encoded representation of it to other nodes for storage, subject to a given total storage budget. A data collector node subsequently attempts to recover the original data object by contacting other nodes and accessing the data stored in them. By using an appropriate code, successful recovery is achieved when the total amount of data accessed is at least the size of the original data object. The goal is to find an allocation of the given budget over the nodes that optimizes the recovery delay incurred by the data collector; two objectives are considered: (i) maximization of the probability of successful recovery by a given deadline, and (ii) minimization of the expected recovery delay. We solve the problem completely for the second objective in the case of symmetric allocations (in which all nonempty nodes store the same amount of data), and show that the optimal symmetric allocation for the two objectives can be quite different. A simple data dissemination and storage protocol for a mobile delay-tolerant network is evaluated under various scenarios via simulations. Our results show that the choice of storage allocation can have a significant impact on the recovery delay performance, and that coding may or may not be beneficial depending on the circumstances.
Year
DOI
Venue
2011
10.1109/ISIT.2011.6033779
international symposium on information theory
Keywords
DocType
Volume
delays,mobile radio,network coding,optimisation,probability,protocols,data collector node,distributed storage allocation,encoded distributed storage representation,mobile delay-tolerant network,mobile storage node network,optimal recovery delay minimization,optimal symmetric allocation,original data object,probability maximization,simple data dissemination,source node,storage protocol
Conference
abs/1106.2581
ISSN
ISBN
Citations 
2157-8095 E-ISBN : 978-1-4577-0594-6
978-1-4577-0594-6
5
PageRank 
References 
Authors
0.53
11
3
Name
Order
Citations
PageRank
Derek Leong116110.86
Alexandros G. Dimakis273941.27
Tracey Ho3435.88