Digital Forensic Certification Practice Exam

What process is often used to ensure that original files remain untouched during forensic examinations?

1. Logical acquisition

2. Bit-stream imaging

3. Data wiping

4. Disk copying

The correct answer is: Bit-stream imaging

Bit-stream imaging is the process that is primarily utilized to ensure that original files remain untouched during forensic examinations. This method involves creating a complete and exact copy of a storage device, including all files and the file system structure, while preserving the integrity and the original state of the original device. By capturing a bit-for-bit image, investigators can analyze the copied data without altering or damaging the original evidence. This fidelity is crucial in forensic investigations, as it allows for the examination of data, including deleted files and unallocated space, while maintaining a valid chain of custody for legal proceedings. In contrast, other processes do not maintain the same level of fidelity or protection for original data. For instance, logical acquisition may not copy all data, particularly deleted or hidden files, while disk copying can sometimes risk altering the original data if not done carefully. Data wiping is aimed at erasing data, which definitively does not preserve any original files. This is why bit-stream imaging is the preferred technique in forensic contexts.