Identify the method utilized by Ruben in the above scenario.
Definition
Bit-stream imaging (also called disk imaging or forensic imaging) is the process of creating an exact, sector-by-sector duplicate of an entire storage media — including all partitions, deleted files, slack space, and unallocated regions — into a single image file. The result is a perfect binary clone of the original.
How It Works
A forensic tool (e.g., dd, FTK Imager, or EnCase) reads every single bit from the source drive sequentially. Each sector — including empty, deleted, and unallocated ones — is copied to the image file. A write-blocker is typically used to ensure the original drive is never modified. A cryptographic hash (MD5/SHA-256) is computed on both source and image to verify integrity.
Why It Matters
In digital forensics, maintaining the integrity of evidence is legally critical. Bit-stream imaging lets investigators work on the cloned copy while the original evidence remains untouched and uncontaminated. This preserves chain of custody and ensures findings are admissible in court. Deleted files reside in unallocated sectors — only bit-stream imaging captures all of them.
Real-World Example
A law enforcement agency seizes a suspect's laptop. The forensic team uses FTK Imager to create a bit-stream image of the hard drive. Working solely on the image, they discover deleted chat logs and photos that still existed in unallocated sectors. The original drive, sealed in an evidence bag, is never powered on again — ensuring its admissibility in court.
Key Takeaway
When you need an exact, forensically sound clone of an entire drive — including deleted files and hidden data — use bit-stream imaging. Unlike logical acquisition (which only copies existing files) or sparse acquisition (which skips empty blocks), bit-stream imaging is the gold standard for preserving every single bit of evidence without contaminating the source.