What is Encryption? Learn the basic concepts

What is encryption? What is cryptography? If you are interested in the latest hot topic of cryptocurrency, this is the article meant for you to get your basics right for understanding the concept of encryption. 

What is Encryption? 

Encryption is defined as the process of encoding information in a way that a snoop could not access the information unless they are in possession of a special decryption key.  Encryption is a process which is used everywhere, right from daily banking activities and transactions to your PC's hard disk.  

Types of Encryption 

Presently, there are two main methods to perform encryption. These are: 

  1. Symmetric cryptography or shared secret encryption 
  2. Public key encryption or asymmetric cryptography 

The first method, I.e. symmetric cryptography is being used since ancient times in Egypt. This method of encryption uses a secret key which is termed as shared secret. This key helps mishmash the data into illegible babble. On the other side, the receiver needs the secret (shared) key to decipher the data, I.e. encryption algorithm. If you change the key, you can change the results of the encryption. Because the same secret key is used on both ends, I.e. between sender and receiver, this method is termed as symmetric cryptography. 

symmetric cryptography

To keep the communication error free, the secret key must be transferred and communicated securely without error. There is a chance for your enemy to intercept the message, if the enemy is able to intercept the key.  

To make it more secure, Whitfield Diffie, Martin Hellman and Ralph Merkle came up with a system called public key encryption (PKE), also known as asymmetric cryptography. Asymmetric cryptography uses an encryption that divides the key into two smaller keys. Out of these, one key is kept private and one is made public. The sender's message is encrypted by using recipient's public key. The decryption can be done by the recipient using his/her private key.  

asymmetric cryptography

Asymmetric cryptography is done with the help of one-way functions. In terms of mathematics, one-way functions are the ones which are easy to compute in one direction but very very difficult to compute in the reverse direction. This is how the public key is published, by deriving it from private key. Because the method uses one-way functions, it is very hard to derive private key going backwards, from public key. One of the most common ways to look at an one-way function is factoring large prime numbers. It is very easy to multiply two prime numbers and find their product. But it is almost impossible to determine which of the two numbers are the factors from the product. If this was possible then the use of public key encryption would become obsolete today.  

I hope you have got a fair idea of what is encryption and the two types of encryption used today. In the next article, we will talk about types of ciphers.