StealthGuard: Proofs of retrievability with hidden watchdogs

Azraoui, Monir; Elkhiyaoui, Kaoutar; Molva, Refik; Önen, Melek
ESORICS 2014, 19th European Symposium on Research in Computer Security, September 7-11, 2014, Wroclaw, Poland

This paper presents StealthGuard, an efficient and provably secure proof of retrievabillity (POR) scheme. StealthGuard makes use of a privacypreserving word search (WS) algorithm to search, as part of a POR query, for randomly-valued blocks called watchdogs that are inserted in the file before outsourcing. Thanks to the privacy-preserving features of the WS, neither the cloud provider nor a third party intruder can guess which watchdog is queried in each POR query. Similarly, the responses to POR queries are also obfuscated. Hence to answer correctly to every new set of POR queries, the cloud provider has to retain the file in its entirety. StealthGuard stands out from the earlier sentinel-based POR scheme proposed by Juels and Kaliski (JK), due to the use of WS and the support for an unlimited number of queries by StealthGuard. The paper also presents a formal security analysis of the protocol.

DOI
Type:
Conference
City:
Wroclaw
Date:
2014-09-07
Department:
Digital Security
Eurecom Ref:
4349
Copyright:
© Springer. Personal use of this material is permitted. The definitive version of this paper was published in ESORICS 2014, 19th European Symposium on Research in Computer Security, September 7-11, 2014, Wroclaw, Poland
and is available at : http://dx.doi.org/10.1007/978-3-319-11203-9_14

PERMALINK : https://www.eurecom.fr/publication/4349