Blockchain for Business 2019

Types of cryptography

Now, we'll introduce some important concepts that will help you understand cryptography's role in the world of blockchain.

Cryptographic cyphers are encrypted and decrypted with keys. These keys are basically secret pieces of information or parameters, which typically look like strings of characters. Think about something such as a password or passphrase that locks and unlocks access to an encrypted message. These are actually keys to the cryptographic algorithms and help convert ordinary information (called plain text) into unintelligible text (called ciphertext) and vice versa. This is shown in the following diagram:

There are two main types of cryptography:

• Symmetric (also known as secret key cryptography): This ...