Visible to the public PTAD:Provable and Traceable Assured Deletion in Cloud Storage

TitlePTAD:Provable and Traceable Assured Deletion in Cloud Storage
Publication TypeConference Paper
Year of Publication2019
AuthorsZhang, Mengyu, Zhang, Hecan, Yang, Yahui, Shen, Qingni
Conference Name2019 IEEE Symposium on Computers and Communications (ISCC)
Date PublishedJuly 2019
ISBN Number978-1-7281-2999-0
Keywordsassured deletion, chaincode, cloud computing, cloud storage, data deletion, data integrity, data integrity checking, deleted data, design algorithms, Distributed databases, efficient deletion method, formal verification, Hyper-ledger Fabric, incomplete deletion, overwriting stage, privacy, provable, provable and traceable assured deletion, PTAD, PTAD scheme, pubcrawl, Scalability, storage management, traceable, unlinking stage, verification stage

As an efficient deletion method, unlinking is widely used in cloud storage. While unlinking is a kind of incomplete deletion, `deleted data' remains on cloud and can be recovered. To make `deleted data' unrecoverable, overwriting is an effective method on cloud. Users lose control over their data on cloud once deleted, so it is difficult for them to confirm overwriting. In face of such a crucial problem, we propose a Provable and Traceable Assured Deletion (PTAD) scheme in cloud storage based on blockchain. PTAD scheme relies on overwriting to achieve assured deletion. We reference the idea of data integrity checking and design algorithms to verify if cloud overwrites original blocks properly as specific patterns. We utilize technique of smart contract in blockchain to automatically execute verification and keep transaction in ledger for tracking. The whole scheme can be divided into three stages-unlinking, overwriting and verification-and we design one specific algorithm for each stage. For evaluation, we implement PTAD scheme on cloud and construct a consortium chain with Hyperledger Fabric. The performance shows that PTAD scheme is effective and feasible.

Citation Keyzhang_ptadprovable_2019