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Modern data privacy regulations such as GDPR, CCPA, and CDPA stipulate that data pertaining to a user must be deleted without undue delay upon the user’s request. Existing systems are not designed to comply with these regulations and can leave traces of deleted data for indeterminate periods of time, often as long as months. We developed Lethe to address these problems by providing fine-grained secure deletion on any system and any storage medium, provided that Lethe has access to a fixed, small amount of securely-deletable storage. Lethe achieves this using keyed hash forests (KHFs), extensions of keyed hash trees (KHTs), structured to serve as efficient representations of encryption key hierarchies. By using a KHF as a regulator for data access, Lethe provides its secure deletion not by removing the KHF, but by adding a new KHF that only grants access to still-valid data. Access to the previous KHF is lost, and the data it regulated securely deleted, through the secure deletion of the single key that protected the previous KHF.
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WAS-Deletion: Workload-Aware Secure Deletion Scheme for Solid-State Drives
Due to the intrinsic properties of Solid-State Drives (SSDs), invalid data remain in SSDs before erased by a garbage collection process, which increases the risk of being attacked by adversaries. Previous studies use erase and cryptography based schemes to purposely delete target data but face extremely large overhead. In this paper, we propose a Workload-Aware Secure Deletion scheme, called WAS-Deletion, to reduce the overhead of secure deletion by three major components. First, the WASDeletion scheme efficiently splits invalid and valid data into different blocks based on workload characteristics. Second, the WAS-Deletion scheme uses a new encryption allocation scheme, making the encryption follow the same direction as the write on multiple blocks and vertically encrypts pages with the same key in one block. Finally, a new adaptive scheduling scheme can dynamically change the configurations of different regions to further reduce secure deletion overhead based on the current workload. The experimental results indicate that the newly proposed WAS-Deletion scheme can reduce the secure deletion cost by about 1.2x to 12.9x compared to previous studies.
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- Award ID(s):
- 1812537
- PAR ID:
- 10446654
- Date Published:
- Journal Name:
- ICCD
- Page Range / eLocation ID:
- 244 to 247
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICCD53106.2021.00047
