Digital Forensic Certification Practice Exam

What data acquisition method would typically be used to recover deleted files without altering original data?

1. Sparse acquisition

2. Logical acquisition

3. Bit-stream imaging

4. Data carving

The correct answer is: Bit-stream imaging

The method that enables the recovery of deleted files without altering the original data is bit-stream imaging. This technique creates an exact byte-for-byte copy of a storage device, preserving the entirety of the original data, including deleted files and the underlying file structure. By capturing every bit of data, investigators can keep the integrity of the evidence intact, which is crucial in forensic investigations. Bit-stream imaging is a standard practice in digital forensics, as it ensures that no changes are made to the original data, which could compromise the authenticity and admissibility of the evidence in legal contexts. While other methods exist, they do not achieve the same level of fidelity. Sparse acquisition only captures selected parts of the data, which may not include deleted files, and logical acquisition focuses on the active file system rather than the raw data. Data carving, on the other hand, involves scanning and recovering files based on their file signatures after the data has been partially or entirely deleted, but it operates on the assumption that these files will still be recoverable without the original context. As a result, bit-stream imaging is the most appropriate and reliable method for recovering deleted files while ensuring the original data remains unaltered.