The name given to the algorithm that encrypts and decrypts information.

Cipher

Introduction

Cipher contains algorithms for protecting the confidentiality of data.

A block cipher is basically encryption method that applies a deterministic algorithm along with a symmetric key to encrypt a particular block of text, rather than encrypting one bit at a time.

For example, a common block cipher, AES, encrypts 128-bit blocks with a key of predetermined length: 128, 192, or 256 bits.

Blockchains make use of two such types of cryptographic algorithms, one being the asymmetric-key algorithms, and the other being hash functions

Types of Cyphers

  1. Symmetric-Key Cryptography – In such an encryption method, user takes take a single key into application.  

 This common key is used for both processes, encryption as well as in the decryption process. Using a common single key creates a problem of securely transferring the key between the senders and the receivers.

  1. Asymmetric-Key Cryptography- In such an encryption method, users use a pair of keys, an encryption key, and a decryption key, named public key and private key respectively. 

The key pair that is further generated by this algorithm consists of a private key and a unique public key that is generated using the same algorithm. 

It is also called Public-Key Cryptography.

  1. Hash Functions â€“ Such an encryption doesn’t make use of keys. 

It in fact makes use of a a cipher to generate a hash value of a fixed length from the plaintext. 

It is absolutely impossible for the contents of a plain text to be recovered from the ciphertext.

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