Visible to the public Per-File Secure Deletion for Flash-Based Solid State Drives

TitlePer-File Secure Deletion for Flash-Based Solid State Drives
Publication TypeConference Paper
Year of Publication2019
AuthorsXiao, Tianran, Tong, Wei, Lei, Xia, Liu, Jingning, Liu, Bo
Conference Name2019 IEEE International Conference on Networking, Architecture and Storage (NAS)
Date PublishedAug. 2019
ISBN Number978-1-7281-4409-2
KeywordsCrosstalk, data deletion, File update operations, flash media, flash memories, flash-based solid state drives, globally unique identifier, GUID, Hardware, Invalid Data Block, invalid flash pages, Media, MultiLevel Cell flash memory, nonreal-time secure deletion, Per-file, Per-File Secure Deletion scheme, privacy, Programming, programming crosstalk, PSD-MLC scheme, pubcrawl, Real-time Systems, Resource management, Scalability, secure deletion, Security-TRIM command, Solid State Drive, solid state drives, SSD

File update operations generate many invalid flash pages in Solid State Drives (SSDs) because of the-of-place update feature. If these invalid flash pages are not securely deleted, they will be left in the "missing" state, resulting in leakage of sensitive information. However, deleting these invalid pages in real time greatly reduces the performance of SSD. In this paper, we propose a Per-File Secure Deletion (PSD) scheme for SSD to achieve non-real-time secure deletion. PSD assigns a globally unique identifier (GUID) to each file to quickly locate the invalid data blocks and uses Security-TRIM command to securely delete these invalid data blocks. Moreover, we propose a PSD-MLC scheme for Multi-Level Cell (MLC) flash memory. PSD-MLC distributes the data blocks of a file in pairs of pages to avoid the influence of programming crosstalk between paired pages. We evaluate our schemes on different hardware platforms of flash media, and the results prove that PSD and PSD-MLC only have little impact on the performance of SSD. When the cache is disabled and enabled, compared with the system without the secure deletion, PSD decreases SSD throughput by 1.3% and 1.8%, respectively. PSD-MLC decreases SSD throughput by 9.5% and 10.0%, respectively.

Citation Keyxiao_per-file_2019