Security feature on internet

In this fast growing world internet has given a lot many things to us. Rather we can say that without internet this revolution in our life was not possible. From Money transferring to paying it using different apps. From sending messages to video calls. All these got possible due to internet. But do you know how the message you send to anyone goes to exactly the same person you want to send without knowing of anyone else. How the money transferred goes to the reciever without knowledge to third parties. This is called privacy or in technical term we can say it as cryptography.

Cryptography is study of technique for secure communication in presence of third parties called adversaries. In cryptology protocols are made which are difficult for third parties to break which prevent them from reading the personal message. Modern cryptography exist at the the intersection of discipline of mathematics, computer science, electrical engineering, communication science and physics. Application of cryptology include e commerce, digital currency, chip based payment card, computer password and military communication.

Cryptology prior to modern age was synonyms to encryption which converted information from a readable state to unintelligible nonsense. The sender of an encrypted message share the decoding technique only with the recipient. Modern cryptology is heavily based on mathematical theory and computer science.

Types of cryptology are as follows -:

1. Caesar Cipher -:

   It is one of the earliest known and simpler cipher. In this cipher each letter of plain text is shifted down to a certain alphabet. It can be also called as substitution cipher For example with the shift of 2, A would be replaced by C, B would become D and so on. This is called Caesar Sepa because Julius Caesar used it to communicate with his generals. Plaintext -: How are you? Cipher text -: JQY CTG AQX?

2. Vigenere cipher -:

   It is a method to encrypt alphabetic text using a key which is secret. Without key the message can not be decrypt. For example Key word is 'WEB' Plaintext - SOLOLEARN KEY - WEB Ciphertex - osmwpfwvo W + S = O E + O = S B + L = M W + O = W E + L = P B + E = F W + A = W E + R = V B + N = O

3. Hashing -:

   Hashing means generating value from the text using mathematical function. Hashing is one way to enable security during the process of message transmission when the message is intended for a particular recipient only. A formula generates hash, which helps to protect the security of the transmission against tampering. When a user sends a secure message, a jash of the intended message is generated and encrypted and is sent along with the message. When the message is received, the reciever decrypts the hash as well as the message. Then, the reciever creates another hash from the message. If the two hashes are identical when compared then a secure transmission has occurred.