Cipher

In the context of blockchain and cryptography, a cipher is an algorithm used to encrypt and decrypt data, ensuring secure communication and storage. Ciphers are essential for maintaining privacy, verifying identities, and securing transactions on decentralized networks. They transform readable data (plaintext) into an unreadable format (ciphertext) and back again, using a specific key.

How Ciphers Work in Blockchain

Blockchains rely on ciphers to keep information secure and tamper-proof. When a user sends data, like a transaction, it’s encrypted using a cipher and a cryptographic key. Only someone with the correct key can decrypt the information. Symmetric ciphers use the same key for encryption and decryption, while asymmetric ciphers—like those used in public-private key systems—use two different keys.

Common Types of Ciphers

Blockchains often use asymmetric ciphers such as RSA and elliptic curve cryptography (ECC). These allow users to verify digital signatures and ensure that transactions are authorized by the rightful key holders. Hash functions, like SHA-256, while not technically ciphers, also play a vital role in securing blockchain data.

Why Secure Encryption Matters

Ciphers help prevent unauthorized access, protect user identities, and ensure that data stored on the blockchain can’t be altered without detection. Without encryption, the entire trust model of decentralized networks would collapse.