New proofs of retrievability using locally decodable codes

Julien Lavauzelle (1, 2) , Françoise Levy-Dit-Vehel (1, 2, 3)

1 LIX - Laboratoire d'informatique de l'École polytechnique [Palaiseau]
2 GRACE - Geometry, arithmetic, algorithms, codes and encryption
3 U2IS - Unité d'Informatique et d'Ingénierie des Systèmes

Proofs of retrievability (PoR) are probabilistic protocols which ensure that a client can recover a file he previously stored on a server. Good PoRs aim at reaching an efficient trade-off between communication complexity and storage overhead, and should be usable an unlimited number of times. We present a new unbounded-use PoR construction based on a class of locally decodable codes, namely the lifted codes of Guo et. al.. Our protocols feature sublinear communication complexity and very low storage overhead. Moreover, the various parameters can be tuned so as to minimize the communication complexity (resp. the storage overhead) according to the setting of concern.

Mots clés: data storage; proofs of retrievability; locally decodable codes; lifted codes; cryptographic protocols

Domaines: Informatique [cs]; Cryptographie et sécurité [cs.CR]; Théorie de l'information [cs.IT]

Julien Lavauzelle, Françoise Levy-Dit-Vehel. New proofs of retrievability using locally decodable codes. International Symposium on Information Theory ISIT 2016, Jul 2016, Barcelona, Spain. pp.1809 - 1813, ⟨10.1109/ISIT.2016.7541611⟩. ⟨hal-01413159⟩