“CRYPTOGRAPHY — Making sense out of the unintelligible”

Codebreakers are linguistic alchemists, a mystical tribe attempting to conjure sensible words out of meaningless symbols — writes Simon Singh in THECODEBOOK.

A code is constantly under attack by codebreakers trying to identify it’s weaknesses. When codebreakers develop a new method that reveals a code’s weakness, then the code is no longer useful or of any importance. It either extincts completely or evolves into a new stronger code. The notion of extinction of a particular code has almost vanished, as the development in codes to make them resistant to attacks have grown with the evolution of the several new code-making techniques. There’s a battle going on between codemakers and codebreakers that inspired some remarkable scientific breakthroughs. The codemakers have been and are continually striving to construct even stronger codes for defending communications, while codebreakers have almost always invented even powerful methods for attacking them. The battle is still going on.

'A man is crazy who writes a secret in any other way than one which will conceal it from the vulgar’.

Information being a valuable commodity, and as the communication revolution changes every now and then, so does the process of encoding messages, known as encryption which plays an important role in everyday life. The networks we are surrounded with show us the beauty of cryptography. From phone calls to emails that pass through various computers, they form a communication network which would’ve been intercepted with ease thus jeopardising our privacy but with cryptography in our hands, everything transmitted along these networks is encrypted and can be decrypted only by the intended recipient.

Cryptography in essence is more than the codes, ciphers and crossword puzzles.

Cryptography itself can be divided into two branches, known as transposition and substitution. In transposition, the letters of the message are simply rearranged, thereby generating an anagram. This method is insecure for short messages because of the limited number of ways of rearranging the letters. A form of transposition was seen being embodied on the surface of the first ever military cryptographic device, “the spartan syctale” from the fifth century B.C.

Mathematics is as important to the strong use of cryptography as bits are to computers.

A various number of fields in cryptography has emerged with time. We have Symmetric, Asymmetric, Quantum, Post Quantum,Homomorphic, Lattice based and Lightweight cryptography as some of the fields. Extensive research is being done across all the fields using the interdisciplinary approach. Symmetric cryptography involves the use of a key known as the “secret key” which is used in the process of encryption and decryption. While as the Asymmetric cryptography approach involves the use of two keys rather than one. Private key and Public key. As the name suggests, Public key is kept open to public along with the algorithm used while the private key is private for the communicating parties involved.

One of the basic principles of modern cryptography is known as the “Kerchoff’s principle” which states : that the strength of the encryption algorithm used, should totally depend on the key even if the algorithm is made public.

The involvement of Cryptography is almost everywhere, from our browsers to our mobile phones, everything is embodied with cryptography. From the use of groups and fields in the symmetric and assymetric cryptography to the use of lattices in Lattice based Cryptography. Cryptography has seen it all. As we are almost in the age of Quantum computers, the research is being conducted to make sure that the available cryptographic primitives stand the attacks from the computing power of Quantum computers. The Post-Quantum era is being looked upon as a strong contender to the Quantum era.

There are two types of encryption: one that will prevent your sister from reading your diary and one that will prevent your government.

It’s your job to choose your type of encryption. Though you’re not sure of when it’ll be broken. As Noam chomsky said:

Somebody will be able to overcome any encryption technique you use!



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Aaqib Bashir

Aaqib Bashir


I used to be a Researcher sometime back, now I write code for a living. Backend Engineer