TASecure: Temperature-aware secure deletion scheme for solid state drives

With the increasing concerns of security, the secure deletion for SSDs becomes very costly due to its out-of-place update (i.e., an update is performed in a new location leaving the old data un-touched). Some previous studies used a combined erase-based and cryptography-based method to find a heuristic deletion scheme. However, the deletion overhead is still large since a key may be associated with too many pages. Therefore, how to reduce the secure deletion overhead further is becoming an interesting research issue. In this paper, a temperature-aware secure deletion scheme (TASecure) is proposed. Data with the same temperature are stored in the same region in order to reduce the overhead of secure deletion. The temperature of a data is referred to the frequency of the data is updated. Moreover, the regions based on their temperature are associated with different numbers of keys and are applied with different secure deletion schemes. Finally, the experimental results indicate that our proposed secure deletion scheme can reduce the secure deletion cost about 1.2x to 19x compared to previous studies.