Symmetric Encryption

Symmetric encryption is a widely used data encryption technique that involves data being encrypted and decrypted using a single secret key.

It is one of the most used encryption techniques and also one of the oldest, dating back to the times of the Roman Empire. The Caesar cipher, named after the dictator Julius Caesar, was used to protect military correspondence and is one of the most famous historical examples of symmetric encryption.

Symmetric cryptography is still used in many major industries such as defense, aerospace, finance, and healthcare. In many situations where protecting the sensitive data of a person, company or organization is of utmost importance, symmetric encryption can play a very important role.

Unlike symmetric encryption which uses the same secret key to encrypt and decrypt data, asymmetric encryption—also known as public key cryptography—uses linked pairs of public and private keys. These are used to protect information and only make it accessible to authorized senders and recipients.

If two subjects—say, Alice and Bob—want to exchange confidential data using a means of communication that is intrinsically insecure such as the Internet, they can use asymmetric encryption to send their respective public keys to each other. Alice will use Bob’s public key to encrypt files since it is only intended for Bob and send him the data in encrypted form. Upon receiving the file, Bob will use his private key (no one else knows it) to decrypt the file and access the content sent by Alice.