The importance of write blockers
Once our physical evidence has been properly documented and collected, we can begin the forensic acquisition of digital evidence. I’ll mention this a couple of times to drive the point home, but the original evidence should only be used to create forensic copies or images, which will be discussed later in this chapter and again in other chapters.
Examination and analysis should only be performed on forensic copies/images of the data and not on the original data or evidence, as working on original evidence can, and usually will, modify the contents of the medium. For instance, booting a seized laptop into its native operating system will allow data to be written to the hard drive and may also erase and modify contents contained in the RAM and paging file.
To prevent this from happening, the use of a write blocker must be employed. Write blockers, as the name suggests, prevent data from being written to the evidence media. Write blockers...
