What are the two types of cryptographic algorithms?

What are the two types of cryptographic algorithms?

• A. Hashing and Encoding
• B. Symmetric Encryption and Asymmetric Encryption
• C. Public-key and Private-key encryption
• D. Stream and Block

Answer: (B)

Cryptographic algorithms are categorized by how keys are used: symmetric encryption and asymmetric encryption. In symmetric encryption, the same secret key locks and unlocks the data, which makes it fast and suitable for large amounts of data, but you have to share the key securely with anyone who should decrypt it. In asymmetric encryption, you have a key pair—public and private. The public key encrypts, the private key decrypts, enabling secure key distribution and digital signatures without sharing a secret key in advance. Because of this, many systems combine both: data is encrypted with a fast symmetric key, and that key is sent securely by encrypting it with the recipient’s public key. Other terms describe different ideas: hashing and encoding aren’t encryption algorithms, and stream versus block refers to how a cipher processes data rather than to two broad types of cryptographic algorithms.

Cryptographic algorithms are categorized by how keys are used: symmetric encryption and asymmetric encryption. In symmetric encryption, the same secret key locks and unlocks the data, which makes it fast and suitable for large amounts of data, but you have to share the key securely with anyone who should decrypt it. In asymmetric encryption, you have a key pair—public and private. The public key encrypts, the private key decrypts, enabling secure key distribution and digital signatures without sharing a secret key in advance. Because of this, many systems combine both: data is encrypted with a fast symmetric key, and that key is sent securely by encrypting it with the recipient’s public key.

Other terms describe different ideas: hashing and encoding aren’t encryption algorithms, and stream versus block refers to how a cipher processes data rather than to two broad types of cryptographic algorithms.