Group-oriented Proofs of Storage

Abstract

We introduces and formalizes the notion of group-oriented proofs of storage (GPoS). In GPoS, each file owner, after being authorized as a member by a group manager, can outsource files to a group storage account maintained by an untrusted party, for example, a cloud storage server, while anyone can efficiently verify the integrity of the remotely stored files without seeing the files. The file owner's identity privacy is preserved against the cloud server while the group manager can trace the one who outsourced any suspicious file for liability investigation. By novelly identifying and exploiting several useful properties, that is, homomorphic composability and homomorphic verifiability in some signatures, we propose a generic GPoS construction relying on the security of the underlying signature scheme and the hardness of the computational Diffie-Hellman (CDH) problem. Following the generic construction, we instantiate a concrete GPoS scheme with the well-known Boneh-Boyen short signature. By leveraging the polynomial commitment technique, the proposed GPoS proposal is optimized with constant-size bandwidth consumption in proof of storage by the cloud server. Theoretical analyses and comparisons show that our GPoS proposal is advantageous over existing PoSlike schemes in user privacy, public audibility and/or performance in a multi-user setting.

Improved group‐oriented proofs of cloud storage in IoT setting

“…A GPoS scheme consists of the following algorithms: ( g p k , g s k )← S e t u p (1 λ ), s k l ← K e y E x t ( g p k , g s k , i d l ), ( τ , F ∗ )← P r F i l e ( g p k , s k l , F ), C ← C h a l l ( g p k , τ ), R ← P r f G e n ( g p k , F ∗ , C ), and 0/1← V e r i f y ( g p k , τ , C , R ). The detailed definition of these algorithms can be found in Wang et al's paper ( g p k , g s k )← S e t u p (1 λ ).…”

“…Wang et al proposed group‐oriented proofs of storage; here, we first review the generic construction and the instantiation, which can be seen in Figure (the detailed meaning of some parameters like , Σ, , and Q can be seen in the work of Wang et al).…”

“…Compared with Wang et al's proposal, our improved GPoS scheme mainly changes the underlying algebraic field to , and the order of multiplicative cyclic groups is converted to the composite order N = p 1 q 1 . Assume that the length of p is 512 bit, and the length of N is 1024 bit.…”

“…In this paper, we focus on group-oriented proofs of storage. Wang et al in AISACCS'15 first proposed the concept of group-oriented proofs of storage (GPoS), 24 and recently, Wei et al 25 also…”

“…In this paper, we focus on group‐oriented proofs of storage. Wang et al in AISACCS'15 first proposed the concept of group‐oriented proofs of storage (GPoS), and recently, Wei et al also proposed a group‐based cloud auditing scheme, but, in this paper, we show there are some flaws in their schemes.…”