After having done numerous posts on Information security, here is another basic and elementary concept in Information security – ‘Cryptography’. The concept of Cryptography also encloses encryption and decryption.
Like any other subject, the field of Cryptography is another massive ocean of information. It is the technique of hiding information to bolster secure communication. Cryptographic techniques are an absolute necessity in this digital age where any information can be snooped on. These are a few basic concepts related to Cryptography:
‘Plaintext’ is the basic message that needs to be transmitted without being observed. The message when encrypted is known as ‘ciphertext’. ‘Encryption‘ is the process of converting the ‘plaintext’ message to encoded form to prevent hacking.
The message is then ‘decrypted’ to get the original message. The process of encrypting and decrypting a message is done by means of an ‘algorithm’. A ‘key’ is used along with the algorithm to encrypt and decrypt the message.
There are two types of encryption – symmetric encryption and asymmetric encryption. Symmetric encryption is defined as the process when both the sender and receiver use the same key. Asymmetric encryption is defined as the process when both the sender and receiver use different keys. In addition to this, symmetric encryption and decryption algorithms are based on two principles, substitution principle and transposition principle
In the substitution principle, the letters, characters or bits are substituted for other letters, characters or bits. The most popular and classic example of the substitution cipher is the ‘Caesar cipher’, which I have already written about.
We have seen the basics of Cryptography, encryption and decryption in this post. Join me as I uncover more technical topics…