A Brief History of Cryptography

“The world runs on codes and ciphers John. From the Million-pound security system at the bank to the Pin machine you took exception to. Cryptography inhabits our every waking moment” — Sherlock Holmes

The desire of secrecy has led Nations to turn to cryptography for effective and safe communication by implementing advanced encryption methods. At the same time rival nations have invested resources to break into these encryptions, steal secrets and gain an upper hand.

There is a lot more to cryptography than what meets the eye, in fact it’s not something that’s of use only on a large scale like powerful nations and wealthy corporations, but cryptography affects our lives more than we think it does. From the safety of our hard-earned money in the bank to the safety of our personal photographs, all of it relies on this sinister sounding word “Cryptography”. It is defined as the art of creating a method to expose or disguise Information Cryptographers are the people who create methods to disguise (encrypt) Information and Cryptanalysts are the people who create methods to expose (decrypt) Information.

An interesting incident in the History of Cryptography can be dated back to 16th century England, when an assassination plot against the Queen was being planned. The traitors used a special encrypting method known as “nomenclators” (alphabets are replaced by special symbols) in their letters.

Unfortunately, the man, these men trusted to deliver their letters, turned out to be a double agent, and redirected all of the letters to the Intelligence Agency responsible for the Queen’s security, The agency had access to world-renown cryptanalysts and convicted them of treason.

Nomenclators were soon outdated when a new method of solving it known as “Frequency method” was introduced. It compared the frequency of the symbols in the message with the original alphabets and eventually decrypted it.

Eventually a new method came into existence known as Vigenere Cipher. This particular cipher baffled the best minds of that era, although simple to apply but painfully hard to solve, then came along Charles Babbage a.k.a Father of Computers. He solved the famous Vigenere Cipher using basic math principles. And once again cyptanalysts were ahead of cryptographers.

This was the era of the World War 2, and nations desperately tried to create unbreakable encryption methods. Finally Germany made a breakthrough and created a famous electro-mechanical rotor encrypting machine known as the Enigma Machine which used electrical circuits and mechanical rotors to scramble alphabets. This was orders of magnitude harder and faster than older basic methods and gave Germany an upper hand over France for 13 years.

After many efforts of France and Poland combined, including sending secret agents to Germany and obtaining valuable information, they eventually cracked it. One of the biggest contributors was Sir Alan Turing, widely known as the Father of Artificial Intelligence. In the effort of somehow decrypting the Enigma Machine, Turing created a machine known as “The Bombe” which deciphered the messages sent by German Navy and Air force. Unknowingly, he had created the most basic form of what we know as a computer.

This trend of famous cryptographers being mentioned as the founders of Computer Science makes sense, since the very existence of computers were for the use of cryptography, since it demanded machines that could perform complex calculations in a matter of seconds. So, it’s safe to say that it was cryptography that gave birth to the vast field known as Computer Science.

Coming back to the Enigma Machine, a Top-Secret letter sent from Germany to Mexico was intercepted by France, in which the president of Germany had ordered the President of Mexico to attack America with the help of Japan. This move was made by Germany to ensure that America does not get involved in the war, and makes it easier for the Nazis (Germans) to capture Britain and France.

As soon as this letter fell in the hands of the French, they informed America and then the war took place as we all know, and thus a nation was victorious with the help of cryptography.

Soon after the world war ended, an infamous project of America’s ARPA (Advanced Research Project Agency) to connect the military computers, led to what we know as the internet today. The advent of the internet was undoubtedly one of the most important events in mankind’s history.

It meant that now anyone from anywhere in the world could e-mail any other person. Although this was a good thing, but this also meant that anyone from anywhere from the world could read your personal emails. This created a concern and in turn created a huge demand for advanced unbreakable encrypting methods.

Up until World War 2 cryptography consisted only of symmetric ciphers (i.e. The same key is used for encryption and decryption). Modern cryptography arose between 1970 and 1980, asymmetric cryptography(i.e. A different key is used for encryption and for decryption). After many failed attempts, finally a secure asymmetric cryptography method known as RSA (Rivest-Shamir-Adleman) system was created, which has been known to be unsolvable up to date.

Asymmetric cryptography was a huge success, since it had two keys, one to encrypt the information (public key) and one to decrypt it (private key). The encrypting key would be made public so that you could encrypt information intended for that particular person and since his decryption key was only known to him, only he would be able to decrypt it.

But there was a problem with RSA, it took to much memory to encode information(around 3000bits). In the early 2000’s, a new form of cryptography which used much less memory (128bits) was introduced known as Elliptic curve cryptography(ECC).

The only known threat to the strong ECC system is Quantum Computers, even the fastest computers of today’s era are like a broken abacus in front of Quantum Computers. Theoretically it would take minutes for a Quantum Computer to decrypt any encryption existing in the world.

This poses a serious threat to nations and businesses having valuable information, but fortunately there also exists something called Quantum Encryption, and as you guessed this is a very secure encryption even Quantum Computers cannot break, of course theoretically, since cryptanalysts have always found a way, whether they do it this time or not, remains to be seen.

The RSA and ECC system created such anonymity, that it ensured that human rights activists and other oppressed people could communicate without getting persecuted and fight for their rights.

On the other hand, it is a well-known fact that organized crime members are some of the most advanced users of strong encryption. The Cali drug cartel is famous for using high-end encryption in communicating their drug deals.

For this reason cryptography has always been a center for hot debates, on one side if the government allows strong encryption it will help terrorists and criminals to communicate and on the other hand if it’s not allowed it breaches the fundamental right of privacy.

Rivest, one of the founders of the RSA system gave an amazing analogy for this case, “A pair of gloves are available almost everywhere in the world, Good men use it to protect their hands but bad men use them to ensure they don’t leave fingerprints. This does not mean that the government should ban gloves.”

This debate is likely to go on for a long time, there will be many different solutions to this problem, but in the end it is on the people to decide whether they trust the government or desire their privacy.

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