Problems
Problem 1: Cryptanalysis (in the lab)
Download this file (cipher1.txt) and find the cipher-text assigned to your group. Perform cryptanalysis to (1) identify the cipher used to encrypt the data, (2) find the encryption key, and (3) decrypt the text. Submit a report that contains the following:
- (2 points) The recovered plain text (exactly as recovered, no need to add spaces or punctuation)
- (2 points) The name of the cipher,
- (2 points) The key, and
- (2 points) A brief description of the steps you took for recovering the key, including a (Github) link to any code you developed to solve the problem.
Problem 2: Cryptanalysis (at home)
First, familiarize yourself with the Playfair cipher by watching the videos below:
Then, download this file (cipher2.txt) and find the cipher-text assigned to your group. The cipher-text is encrypted with Playfair. Your job is to find the encryption key, and then decrypt the text. Submit a report that contains the following:
- (5 points) The recovered plain text (exactly as recovered, no need to add spaces or punctuation)
- (2 points) a brief explanation of how one could infer that the text is encrypted with Playfair (in case it was not known),
- (3 points) the recovered key, and
- (7 points) a brief description of the steps you took for recovering the key (include a Github link to any code you developed to solve the problem).