What is Cryptanalysis & how it works?

Cracking the code

The study of methods to decipher the meaning of encrypted messages without access to the information required to do so is Cryptanalysis. It includes decryption and analysis of cipher codes and encrypted text with a focus to understand how they work, find and improve techniques for defeating or weakening them.

Cryptanalysis is also called as code breaking or cracking the code. It is more technical and advanced study of breaking codes. It uses mathematical formulas to find algorithm vulnerabilities and crack into cryptography or information security systems.

Cracking the code of this kind is exceedingly important especially in our world that is highly dependent on technology. Cryptology is constantly being pushed and pulled forward by both cryptographers trying to secure an edge with the coded messages and by cryptanalytic who are trying to break the code to unravel information.

What does a cryptanalyst do?

A cryptanalyst develops mathematical methods and codes that protect data from computer hackers. They are responsible to ensure that the sensitive data transmitted through the computer networks are secure and encrypted so that these information are not accessed by hackers. It includes keeping online transaction; credit card banking and ATMs, safe for use.

Another major function is to protect communication lines and wireless networks using ciphers or encryption codes based on computational number theories and number schemes.

Plainly said, Cryptanalysts are mostly mathematical experts, who can create, set-up and evaluate algorithms designed to solve number theory problems. If a hacker deciphers a code, it is the cryptanalyst’s responsibility to develop new methods for encrypting data as well as to encode messages to conceal sensitive data.

How they do it?

Cryptanalyst have varied types of Ciphers & different methods of Cryptanalysis that can be used to break ciphers and codes. Ciphers and codes have been prevalent in history and they are easiest to crack; however, with computational capability enhanced, the algorithms conceived are super difficult and inconceivable. The most important types of cipher you need to know include:

Caesar Cipher

It is one of the earliest, easiest and simplest form of coding. It was used by Julius Caesar to commonly communicate with his generals by using this type of secret text and hence named after him.

Here each letter is shifted an exact number of letters away from the original letter. For example, using a key of three letters A would become D and E would become H in the coded letter. To decipher the algorithm, the cryptanalyst must figure out the fixed number of letter-shifts that forms the code. Voila , then you would have solved the cipher.

There are only a limited number of letters in the alphabets and you have a fixed twenty five different possibilities; this makes it easy. You can try each possibility until you get readable text. Else a cryptanalyst could use letter frequency to crack the code.

Text Characterization

Another method to find the key to solving a certain text is text characterization. The three main techniques that are used to characterize the text are counting frequency, identifying patterns and using CRANK, the cryptanalysis tool kit.

There are other more complex methods such as the Index of Coincidence which approximates or guesstimates the frequency in which specific letters are distributed in certain languages. A comparison of this, with the code using certain patterns may help discover the key.

Yet one more complicated method is called Quad-gram Statistics. It’s used in the same way i.e. by adding up all the possibilities of cipher text appearing in a particular length… let’s say in a length of four blocks; this will help the cryptanalyst to comprehend how close the code is to a language primarily to true English.

Modern Cryptanalysis

This spectrum is vast, complex and complicated. There are many different modern and unconventional methods of cryptanalysis. One can measure the difference in electricity consumption during securing information on microchip – this technique of timing and differential power analysis over time can provide information about encryption algorithm and help attain more information of other security functions of the chip.

With technology one could be passive and persuasive enough to trick people to give passwords and keys or distract them into using hackable cryptosystem. The Trojan horse virus is another technique to steal key from a computer.

The modern cryptanalyst should be smart enough to outsmart and strong enough to outlast every hack every time, with cutting edge technology being fed into the systems and available to both sides and mostly used by government and by extension nations who are serious about the matter of securing safe channels and networks for communication.