Secure Deletion Module for Flash Storage Data Erasure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current storage systems, such as those using flash memory, face challenges in securely deleting files, as recovered data can expose sensitive information like personal details or secret documents, due to incomplete data erasure processes.
Innovation Solution
A host and storage system implementation that includes a secure deletion module capable of issuing invalidation, unmap, overwrite, and erase commands independently of the operating system, ensuring complete data invalidation and erasure before the file is deleted by the OS, preventing data recovery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a standard deletion operation is performed by the operating system, then the file is removed from the file system, but the data remains recoverable from the storage system
Solution Approach 1:
The secure deletion module performs invalidation and erasure operations on the storage system before the operating system completes its deletion process. By issuing invalidation commands first to mark data as invalid, and then erasure commands to physically erase the data, the system ensures data cannot be recovered even though the OS deletion is still in progress
Solution Approach 2:
The deletion process is divided into distinct phases: invalidation phase where data is marked as invalid, and erasure phase where data is physically erased. This segmentation allows the system to separately handle the logical deletion (OS level) and physical deletion (storage level), ensuring comprehensive data security while maintaining file system integrity
2Reliability
If data is erased from the storage system, then data security is improved, but the deletion process time increases
Solution Approach 1:
The invalidation command is issued first to mark data as invalid before physical erasure begins. This preliminary action allows the system to start the erasure process immediately without waiting for the OS to complete its deletion, overlapping operations to reduce total time
Solution Approach 2:
The erasure process is performed in periodic batches rather than all at once. The secure deletion module issues erasure commands for multiple files in sequence, allowing the storage system to process erasures efficiently without overwhelming the system, thus reducing overall deletion time
Data Source
AI summary
An operating method of a host includes receiving a request for secure deletion of a first file stored in a storage system, providing an invalidation command to the storage system for invalidating data of the first file, providing an erase command to the storage system for erasing invalidated data included in the storage system, and performing a deletion operation, which is executable on an operating system of the host, on the first file which is deleted by the erase command.