A comparison of redundancy techniques for private and hybrid cloud storage

Abstract

File redundancy techniques have been very useful mechanisms for offering fault tolerance and data availability in any kind of storage. Cloud storage is not the exception. This paper presents an evaluation of classical file redundancy techniques implemented in two cloud-storage deployment models, private and hybrid. A small prototype of a private and hybrid cloud storage was implemented for this evaluation. The performance impact when file redundancy is only applied in a private cloud versus when redundancy is also distributed in a public cloud (the hybrid model) is analyzed. Additional to classical file redundancy techniques, an innovative method was evaluated for file redundancy based on an information dispersal algorithm (IDA). The usage of IDA represents a good option for managing sensitive data in hybrid cloud storage. In this technique, only parts of a file need to be sent to the public cloud, avoiding the complete file to be read from outside of the private zone. In this context, there is a trade-off between performance (for reconstructing the original file, it is first necessary to obtain all of its fragments) and the security level that could determine the viability of using IDA. Copyright © 2011 Universidad Nacional Autónoma de México.