We will classify authentication mechanisms described in a set of printed slides according to the taxonomy we saw on class, and rank from the least secure to the most secure. The class will be split in at most 8 groups, each with its own set of slides. There will be two activities in the exercise:
- First, classify all different authentication solutions into the 4 types given. Use the diagram below as a reference example. Consider that a user is authenticating against some service provider, and the classification should be performed from the point of view of the service provider and what authentication factors must be managed by it.
- After all solutions are classified, organize each column from least secure (on bottom) to most secure (on top).
Observation: There is no single correct solution, the point is exactly to discuss the trade-offs. Assume a realistic implementation (not horrible or perfect) working in realistic conditions.
I have a big problem: When preparing this exercise last Monday, I encrypted a very important file. Unfortunately, I forgot to save the key, and now I cannot access the data anymore. Can you help me decrypt it?
This is the command that I used:
$ python encrypt.py plain.txt ciphertext.bin
See decrypt.py for a brute force attack over possible keys.
Use it like this:
$ python decrypt.py 2021-09-20 ciphertext.bin decrypted.txt