Data Erasure Apparatus Using Iterative File Overwriting
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Solution Overview
Problem
Current data erasure methods for storage devices, such as factory reset processes, are unreliable and platform-dependent, posing security risks due to incomplete data removal and potential for data recovery, especially in large-scale IT asset disposition processes.
Innovation Solution
A method involving a data erasure apparatus that connects to storage devices via a file-based protocol, iteratively writes files of varying sizes to occupy and overwrite selected memory regions, using a seed-generated random dataset for verification, ensuring complete data erasure while maintaining the operating system functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If factory reset processes are used to erase data, then device functionality is maintained, but data erasure reliability is poor and data may be recovered
Solution Approach 1:
The patent applies preliminary action by overwriting data multiple times with random patterns before the actual erasure process. This pre-processing ensures that even if the operating system's factory reset fails to completely remove data, the preliminary overwriting has already rendered the data unrecoverable. The method performs multiple passes of random data generation and storage to the target storage regions, ensuring data is destroyed before handover to the OS reset process.
Solution Approach 2:
The patent replaces the mechanical/system-dependent factory reset process with a software-based random data generation and overwriting system. Instead of relying on the operating system's built-in reset mechanisms (which vary by platform and may have security flaws), the invention uses a cross-platform random number generator to create unpredictable data patterns that are written directly to storage, bypassing OS limitations and providing consistent, verifiable erasure across all device types.
2Object-affected harmful factors
If cryptographic techniques are used to erase data, then data security is improved, but encryption key destruction may be incomplete leaving data recoverable
Solution Approach 1:
The patent extracts the data erasure function from the cryptographic key management system. Instead of relying on the OS to destroy encryption keys (which may fail or leave residual keys), the invention directly overwrites the encrypted data on storage with random patterns. This separates the erasure mechanism from key management, ensuring that even if key destruction fails, the actual data on disk is rendered unrecoverable through direct physical overwriting.
Solution Approach 2:
The patent creates multiple copies of random data patterns and writes them to the same storage regions in successive passes. By repeatedly writing different random data copies to the same locations, the method ensures complete overwriting of any residual encrypted data or key material, making recovery impossible even if one pass fails or leaves gaps.
3Adaptability or versatility
If operating system factory reset is used, then device can be re-sold and warranty maintained, but data erasure effectiveness is uncertain and platform-dependent
Solution Approach 1:
The patent implements universality by creating a platform-independent data erasure method that works across all operating systems (iOS, Android, Windows, etc.). The random number generator and overwriting mechanism are implemented in a way that does not depend on any specific OS architecture or file system. This universal approach maintains device reconditioning compatibility while ensuring consistent, verifiable data erasure effectiveness across all platforms, eliminating the platform-dependent variability of OS-specific factory resets.
4Reliability
If multiple passes of random data writing are performed, then data erasure completeness is improved, but processing time increases
Solution Approach 1:
The patent applies partial action by performing a limited number of overwriting passes (typically 3-7 passes) rather than excessive overwriting. Research shows that 3-7 passes of random data overwriting are sufficient to render data unrecoverable with extreme certainty. The method implements this optimized number of passes to achieve complete erasure without unnecessarily extending processing time, balancing reliability with efficiency in high-volume ITAD operations.
Data Source
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AI summary
A method of erasing data using a file-based protocol from a data storage apparatus for repurposing, reallocation to a new user or retirement of the data storage apparatus, the data storage apparatus comprising a memory using a file-based protocol, and the method comprises: receiving one or more signals representative of the available free space of at least one selected region of the memory; iteratively writing files to the at least one selected region of the memory using the file based protocol, wherein: at least one of the files is sized based on at least one of the received signals and the iterative writing of the files comprises writing the files in sequence such that for at least part of the sequence each file is smaller in size than the preceding file of the sequence; and wherein the files are written to collectively occupy all of the at least one selected region of the memory; and the method further comprises receiving an indication that said at least one selected region of memory is full following the writing of said files, and in response to the indication writing at least one further file to said at least one region of memory.