How to tell if your cloud files are vulnerable to drive crashes

This paper presents a new challenge—verifying that a remote server is storing a file in a fault-tolerant manner, i.e., such that it can survive hard-drive failures. We describe an approach called the Remote Assessment of Fault Tolerance (RAFT). The key technique in a RAFT is to measure the time taken for a server to respond to a read request for a collection of file blocks. The larger the number of hard drives across which a file is distributed, the faster the readrequest response. Erasure codes also play an important role in our solution. We describe a theoretical framework for RAFTs and offer experimental evidence that RAFTs can work in practice in several settings of interest. Categories and Subject Descriptors E.3 [Data]: [Data Encryption] General Terms Security Keywords Cloud storage systems, auditing, fault tolerance, erasure codes

• Type: Journal
• Year: 2011
• Where: CCS
• Authors: Kevin D. Bowers, Marten van Dijk, Ari Juels, Alina Oprea, Ronald L. Rivest
• Keywords: CCS 2011, Drive Failures, Fault Tolerance, Security Privacy, Tolerant Manner