Foo - Any Cryptography Fans in Foo?

First person to crack this code completely is going to get a pleasant surprise....

13 15 7 9 78 25 7 13 17 13 26 81 78 85 17 78 78 7 106 17 7 9 108 6 15 81 25 25 15 81 9

7 13 81 13 7 9 13 6 85 85 17 85 78 17 15 78 81 86 65 5 15 25 81 65 17

This message is INDEXED to ISBN 9780745328478 and translate = 13 15 7 9 78 25 7 13 17

Post your answer in the thread and good luck!

42

Karl Marx's lifetime batting average

Translate this message and you will win a titanium membership for life.

Translate this message and you will win a titanium membership for life.


Good job! You'll see a little membership status change in a short moment. :D

Coolness! Thanks, Tom. :thumb:

Translate this message and you will win a titanium membership for life.

So what was your method? How did you crack it?

First person to crack this code completely is going to get a pleasant surprise....

13 15 7 9 78 25 7 13 17 13 26 81 78 85 17 78 78 7 106 17 7 9 108 6 15 81 25 25 15 81 9

7 13 81 13 7 9 13 6 85 85 17 85 78 17 15 78 81 86 65 5 15 25 81 65 17

This message is INDEXED to ISBN 9780745328478 and translate = 13 15 7 9 78 25 7 13 17

Komrad Tom is there something you are not telling us? :lol:

Komrad Tom is there something you are not telling us? :lol:

The Manifesto is the most published book on the planet (It even beats the Bible), and hence, it makes a good key for a cypher. In this case, the cipher is based on the index of that particular edition of The Communist Manifesto from the Pluto Press of London. Look at the index, and the letters are represented as any of the page numbers associated with the first letter of the first word of the letter category in the index. If there is no word associated, I would have inserted a capital letter in the clear, which seriously screws up pattern analysis or frequency analysis for decryption. Using a book cypher does a great job of randomizing and allows a 2 stage public/private key and even multiple layers of encryption equal to or better than PKI encryption.

I just found it funny your choice of the book. :lol:

Anyway your version of cypher is susceptible to statistical approach since the mapping was the same of letter to number. Also since the the mapping does not change I don't believe it means the requirement of CCA. Although the proper algorithm where mapping is not fixed does meet it.

I just found it funny your choice of the book. :lol:

Anyway your version of cypher is susceptible to statistical approach since the mapping was the same of letter to number. Also since the the mapping does not change I don't believe it means the requirement of CCA. Although the proper algorithm where mapping is not fixed does meet it.
But the mapping does change, since in most letter cases, there are as many as 5 pages to choose from where there is an instance of the word. I chose to try to leave it with the same number to represent t, for example, or a, when in the case of a for example, there were 6 page numbers to choose from.

By the way, all ciphers are susceptible to a statistical approach, some are just more difficult than others. I chose the easiest variation in this case.

Harumph!
I have a copy of the Manifesto, but different ISBN.

But the mapping does change, since in most letter cases, there are as many as 5 pages to choose from where there is an instance of the word. I chose to try to leave it with the same number to represent t, for example, or a, when in the case of a for example, there were 6 page numbers to choose from.

Ah right. I just skimmed over it, thought you didn't change it.

Harumph!
I have a copy of the Manifesto, but different ISBN.

Commie. :lol:

So what was your method? How did you crack it?

I looked for patterns. Filled in what I knew...translate = # # # # # # # # #...then used the Wheel of fortune method. There were enough letters given to figure out the rest of the words.