Crypto
CRYPTO Launched
One key to see it all,
Art of esoteric secrecy,
The Panache of mystery.
A billion computers doing a trillion calculations a second - it is not possible to decipher the result of strong cryptography before the end of the universe. Are you ready to take up the challenge, it's only the sheer elegance of the human mind which has the might to unveil the deadliest secrets.
Loose your rationality & let your rusty gears loose, jingle in the disco of grey cells.If you loved cracking codes, demystifying the truth or had a knack for unravelling baffling puzzles or were fascinated by hacking, you are the right place.
It’s your oppurtunity to be the next Sherlock Holmes, embark on a terribly exhilirating journey to fight out in the mightiest of brain wars to emerge as THE MASTER OF THE KEY.
Problem Statement:
A dedicated NASA scientist, 3 successive failed satellite launches, a lurking conspiracy....what follows is a thrilling turn of events that'll test your cryptic powers to the core.
CAN YOU HELP HIM FIND THE TRUTH? CRYPTO AWAITS YOU.....
Basic techniques to solve Crypto:
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Substitution:
This is amongst the simplest of techniques. The characters are mapped to different characters for example ‘p’ in a text message may be replaced by ‘z’. Such maps are generally reversible and hence no two characters(alphabets) would correspond to a same character.
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Permutation:
The alphabets are permuted in a fixed manner by first breaking the text message into blocks of equal size.
Example:
Secret Permutation: 1-->2-->4-->1 . 3-->3
Text Message: This is easy
Cipher: sTih siyesa
In this case, the spaces are also counted as characters. But mostly, we do not permute the spaces.
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Shift:
Each alphabet will be shifted by some fixed number.
Example: A shift by 3 gives: a-->d, b-->e, ...
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Addition Modulo 26:
Example:
Text: ADDING
Secret Key: CAT
Cipher: DEXLMA
Here, A + C = D, D + A = E, .... , T + G (mod 26) = A (When the addition of two alphabets crosses Z, take the remainder, i.e., again start from A as in: Y + C = B)
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Other Simple Techniques of Information Hiding:
Keep thinking. As you proceed, you will get the clear picture. :)
Note: A combination of more than one of he above mentioned techniques can also be used.
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Ways to Attack:
Often you will find some weaknesses in text. While substitution ciphers can be attacked by frequency analysis of alphabets (see wiki) permutations can be attacked by observing ‘mini-anagrams’. Out of a cipher, one may be lucky enough to guess a word or its part permutations can be attacked by observing ‘mini-anagrams’. Work backwards and try getting the key assuming the guess was right. If you start getting something meaningful, you are nearly done. Continue observing and thinking.
Contacts:
| Ankur Guatam | ankg@iitk.ac.in | +91 9935700812 |
| Mrityunjay Kothari | mkothari@iitk.ac.in | +91 9559772670 |
| Nikhil Pangarkar | nikpan@iitk.ac.in | +91 9559753657 |
