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A data sanitization method for mobile devices with NAND flash memory

NAND flash memory is a popular storage device used in mobile devices because it has many advantages such as high-density, lightweight, shock-resistance, non-volatile, and low-power features. NAND flash memory requires flash translation layers (FTLs) to handle its architectural characteristics, such as out-of-place update, erase-before-write feature, and limit of erase count. When data sanitization issues are considered for mobile devices with NAND flash memory, the previous work for hard-disk drives could not work properly for NAND flash memory due to the design of flash translation layers. In the paper, we will propose a data sanitization method which is suitable to completely erase data for mobile devices with NAND flash memory. We will implement a data sanitization application on mobile devices with different typical overwriting algorithms. Then, we will collect the related I/O requests and put the I/O requests into the proposed FTL simulator to verify the feasibility of this method. Based on the experimental results, we can demonstrate that the data sanitization method is suitable to completely erase data for mobile devices with NAND flash memory.