Q1. Which tool or technique from the above list would be most effective for a cryptanalyst to use to decipher a text encrypted with the Caesar cipher, and why?
I personal like all the ways that I saw in the above list. I think that a cryptanalyst would likely to use the Histogram. I personally think it is easier to read and the information that it gives is very valuable. It gives you the frequency and percent on how many times a certain character was used. Which if I think if I was a cryptanalyst this may help me out in deciphering the encrypted text.
Q2. What do you notice about the histogram results when text is encrypted with the Vigenère cipher in comparison to the results of ...view middle of the document...
“The difxference betwexen stupidity and genius is that genius has its liscts”.
Q4. Of the three ciphers discussed (Caesar, Vigenère, Playfair), what are their relative degree of security and why?
When I look at the three ciphers it seems that Vigenera is the most difficult in my opinion especially when you look at the histogram. It has an entropy of 4.17 compared to the other two ciphers. Playfair seems easier to break than all of them but it has a entropy of 4.42 which says it is slightly more difficult to crack so I am up in the air with this one. Caesar would seem to be the next difficult especially when I look at the histogram. It also has a entropy of 4.17. Result list below.
Lab Part 2: Advance Crytography Functions
Q5. For each of the following say whether ECB or CBC would be most appropriate and give a brief explanation as to why.
a. an online bank statement [10 points]
b. an encrypted VoIP session [10 points]
c. viewing of a website using TCP/IP [10 points]
I would think that an online bank account statement would be best if it had the stronger of the two encryption, especially with the type of information that is found on the document. I would say that it would benefit from CBC. CBC doesn’t allow for the patterns that ECB would thus being easier to decipher. When it comes to an encrypted VOIP session you don’t want the encryption so complicated that all the packets can’t be deciphered by the receiver when sent over VOIP. I would use ECB when it comes to VOIP sessions. When it comes to viewing of a website using TCP/ IP- It would depend on the security level you are trying to reach. Anything site that you are viewing and you are using personal information or secret work related information or things that you just don’t want someone to easily decipher I would use CBC encryption. You know with this you will have most security and unlike VOIP you are worried about the packets being sent because most ISP/Websites can handle them.
Q6. What difference do you notice in the block size, discuss whether or not this cipher would be susceptible to statistical analysis and why?
I can see the difference of the block size...