Ensuring Dynamic Data Integrity based on Variable Block-size BLS in Untrusted Environment
Long Chen, Wei Song, Siu‐Ming Yiu, Wenjun Luo · International Journal of Digital Content Technology and its Applications · 2013
Security becomes the major concern when people utilizing cloud computing. One major challenge is to ensure the integrity of data in untrusted environment under the condition of supporting public auditability and dynamic data operation. The paper proposes an improved data integrity verifying protocol to ensure the security of user’s data and promote the verifying efficiency using dynamic Merkle tree with relative index. The protocol is based on an extended security model for untrusted environment where each participant may act as an untrusted role. Furthermore, because BLS based schemes have the advantages of shorter homomorphic signatures than RSA based schemes but with disadvantage of fixed and small block-size, a BLS based scheme with variable block-size is integrated in the protocol. Performances analysis showed that the improved protocol is effective and provides a practical and flexible solution for untrusted environment. The computation complexity of dynamic data operation and integrity verifying reaches O(log n) definitely.