sections 18.1 and 18.2

Difficult: I didn't understand the Hamming distance very well.

Interesting: It's interesting that they've come up with a way to correct errors in code words, etc.

section 2.12

Difficult: I didn't understand the process very well for attacking it

Interesting: It's funny that this is what our reading is for tomorrow since I was actually just talking to someone about Enigma earlier today when I told them I was in a Cryptography class. I think it's interesting (though I guess unsurprising) that the British sold captured machines to former colonies and kept the fact that they had broken it a secret for so long.

Shor's algorithm and section 19.3

Difficult: Shor's Algorithm and the quantum Fourier transformation was kind of confusing

Interesting: The whole idea of a quantum computer was interesting. Especially since the authors said that they aren't yet a reality and yet the ideas are out there on what the computer would be able to do even though it isn't a reality. Also, the internet reading will really interesting to read. Definitely sounded like something you would have written just because of the guy's personality...

sections 19.1 and 19.2

Difficult: It doesn't seem that difficult as far as the key distribution part goes, but I'm still confused about quantum mechanics itself

Interesting: It's really weird/interesting to find out that quantum mechanics has applications in cryptography. The filter/overview of quantum mechanics discussion was interesting

sections 14.1 and 14.2

Difficult: I don't think I understood very well what the heck was going on with the tunnel analogy. how can Peggy always come up the correct side of the tunnel if she doesn't know which way the door opens? I'm confused.

Interesting: the story at the beginning was interesting. It's weird that someone could manage to put a fake atm anywhere period without security/mall officials or whoever asking questions to validate that the machine was legitimate.

Midterm 2 Review

• Which topics and ideas do you think are the most important out of those we have studied?
• What kinds of questions do you expect to see on the exam?
• What do you need to work on understanding better before the exam?
Thinking about the answers to these questions can help guide your study.

I don't know how to solve any of these problems by hand very well at all!! Please go over that in class!

sections 12.1 and 12.2

Difficult: I'm not sure I understand the Shamir threshold scheme very well, but I'm sure with pracetice, I'll be able to understand it better

Interesting: I like the whole you need two people to reconstruct idea. It's a lot like how you need multiple keys to set off those crazy bombs the military uses, etc. I like that it makes it harder for people to find since the pieces are divied up.

sections 9.1-9.4

Difficult: Are we going to have to break any of these? Because I'm not sure I'd be able to until possible after reading later sections that probably go into methods to break them. Though I'm sure they are similar to how we break RSA and ElGamal. I also thought the ElGamal Signature Scheme was kind of complicated, but still kind of like the normal ElGamal encryption method, so maybe it's not as bad as it looks? Could you do examples of these methods in class?

Interesting: I thought it was interesting how the different encryption methods could be modified to create personalized signatures and also that this idea hasn't (explicitly) come up before these sections really. I also thought the difference between the signature with appendix and message recover scheme was interesting.

sections 8.4-8.5 and 8.7

Difficult: I'm kind of confused about how to use the birthday idea to attack different ciphers

Interesting: I found it interesting that they spent so much time talking about the probability of repeating birthdays when almost everyone already knows about the birthday paradox.

sections 8.1-8.2

Difficult: I thought the second hash method would be difficult to do--for long messages, especially.

Interesting: I thought the hash function in 8.2 was interesting because it was more effective than the first one described, I wonder what other hash methods there are that would be more effective.

sections 7.3-7.5

Difficult: I think the Diffie Hellman Key Exchange would to interesting and difficult to encrypt/decrypt by hand for sure, but I also think the Computational Diffie-Hellman Problem would be difficult to compute period. Could you show an example in class?

Interesting: The bit commitment section was really interesting. I had never really thought of it before, but it makes since in some situations that someone would make a bet/prediction or something like that and would not want the other person to know what they sent until a certain day/time. It's kind of like sending a gift before someone's birthday and not wanting them to open it until their birthday, even though it was sent early. I think it's a really cool way to accomplish this, because before, you just had an honor system so to speak, but this way, you can't change the bet/whatever, and Bob can't open it until you give him the 'key' so to speak.