Basic technical information about passwords and encryption
Basic technical information about passwords and encryption
This week’s reading gives you basic technical information about passwords and encryption, and how to recover data protected by these mechanisms. There is also a section on Steganography, which literally translated means “covered writing.” When some people think of steganography, or “stego,” they think of documents or other data files being hidden in other file types (usually image/picture files). Interestingly, the use of stego goes much farther back than the use of computers.
Like cryptology, steganography is used to hide something in something else. So, even though a code breaker can detect the hidden code, they may not be aware that the code actually contains a different message. Cryptography scrambles a message so that it is unreadable, but still visible, while stego camouflages data to hide it or make it undetectable. This course is not meant to teach you about the technical details of encryption or passwords or steganography (entire books are written on each of those subjects), but rather to help you understand their place in the criminal justice process.
If a law enforcement officer obtains a search warrant for digital data, does the warrant give him the authority to break passwords protecting information or to decipher encrypted data? This is a very important question. As many of you have discussed, it is important to make sure you know the limits of the warrant. While an examiner is conducting a search with a properly executed warrant, you may come across other information that is not included in the scope but is still evidence of a crime. For example, imagine an examiner is searching a hard drive for information related to a fraud scheme. While the examiner is looking through the files he comes across a picture that is obviously child porn, but child porn is not addressed in any way by your warrant. What does the examiner do? The proper response is to stop the search and obtain another warrant for evidence related to child pornography. The same thing applies to discovering encrypted data. In a search warrant affidavit there should be an explanation that criminals sometimes encrypt files that contain evidence. Some may even use steganography techniques to hide other files.
This week I would like you to do some research on encryption and steganography.
- List and explain five (5) examples of how steganography were used BEFORE the advent of computers.
- List and explain five (5) examples of how encryption (or cryptology) were used BEFORE the advent of computers.
- Discuss how steganography or encryption could be used legitimately, and
- Why this could cause you a problem as a computer forensic examiner.
Your initial discussion response is due no later than Thursday at midnight. The earlier, the better! Then, reply to at least two fellow student’s original post with thoughtful substantive input that adds to our learning!
