Globalization made the world closer so the Internet made them connected. Internet is so vast that we can’t risk our data security over the internet. Science of Cryptography mainly deals on how we can secure data over Internet through encryption and decryption.
This article will guide you to the basic knowledge of Cryptography. It will help you build up your foundation so that you could charge your brain for higher level of knowledge sharing session.
Origin of Cryptography
Cryptography, which is taken from the Greek words Kryptos which means Hidden or secret and Graphein which means Writing. It means this is the art of secret writing. So we can assume that it first evolved when art of writing or art of conveying information came into picture.
Evolution of the science of Cryptography took place in pre-historic times, which is around 4000 years ago. It was the phase when Egyptians used Hieroglyphy technique to send and receive messages in a secret format.
Roman also invented another technique, called Caesar Shift Cipher to send messages secretly. In this technique they were sending messages by shifting the position of letters back or forth.
For example: If we have to send a reply like MY NAME IS AVINASH.
In Caesar Shift Cipher, we will send above message in the way by shifting the position of letters.
PB QDPH LV DYLQDVK.
Here we shifted letters to next 3rd position in to its alphabets.
Techniques to send information secretly also got improved with the change in time, evolution of culture, birth of new community, advancement in technology and more.
Steganography is another technique to send message secretly. In this technique people used to send messages by putting watermark in the paintings or any picture.
19th Century witnessed the real development in modern cryptographic techniques. Major inventions took birth in this phase only. Various sophisticated approaches came into existence. Electro-mechanical devices and machines came into picture to send encrypted messages. Enigma rotor machine was among them. It efficiently coded the information.
During World War II Cryptography reached its peak of its initial stage of development.
Evolution of Modern Cryptography
Modern technique is fully based on mathematical algorithms, Number theory, Probability and various computational theories. It has various advantages over the traditional one, even though earlier approaches of cryptography acted as the base for the modern technique.
Digital electronics is the foundation of modern cryptographic system which deals on encrypting data in binary bit format. It generates a Secret Key.
What is Secret Key?
It is developed out of mathematical and computational algorithm, which is highly secure. It only involves those parties who are directly responsible to get information after decryption of secret key.
What is Cryptography?
Cryptography is the art & science of securing the information.
It helps us to secure our digital data in any format by providing encryption block. While the information can be retrieved once we decrypt it.
What is Cryptanalysis?
It is the mechanism to study the encrypted information sent through Cryptography.
Objectives of Cryptography
Here are major four objectives we achieve with the help of cryptography:
- Confidentiality- It gives secrecy to our data. It protects our data to read by unauthorized entity.
- Data Integrity- It identifies the occurrence of manipulation in data. It assures the intactness of data.
- Authentication- It assures the message has been sent by verified user. It also makes sure that data is going to verified receiver.
- Non-repudiation- It assures that the sender does not deny after sending the information. It overcomes dispute when any one refuse to take accountability of the information.