Sequential

The ChaCha20 Cipher is a modern symmetric stream cipher designed by Daniel J. Bernstein as an improvement over earlier stream ciphers like RC4. It operates by generating a secure pseudorandom keystream using a combination of a 256-bit key, a 96-bit nonce, and a counter. This keystream is then XORed with the plaintext to produce ciphertext. ChaCha20 is known for its speed, simplicity, and strong security properties, and is widely used in modern protocols such as TLS and VPN systems.

RC4 (Rivest Cipher 4) is a symmetric stream cipher designed to encrypt data by generating a pseudorandom keystream that is combined with plaintext using bitwise XOR operations. Unlike block ciphers such as AES or DES, RC4 operates on data one byte at a time, making it fast and simple to implement. It was widely used in protocols like SSL/TLS and WEP, though it has since fallen out of favor due to discovered vulnerabilities.

The Rabbit Cipher is a high-speed stream cipher designed for efficient software implementation. Unlike block ciphers such as AES or DES, Rabbit generates a continuous keystream that is combined with plaintext using XOR operations to produce ciphertext. Originally developed in 2003 and later submitted to the eSTREAM project, Rabbit is known for its balance of performance and security, making it suitable for real-time encryption scenarios.

The Lorenz Cipher is a machine-based stream cipher developed by the German Army during World War II, primarily for high-level communications such as messages between headquarters. Unlike the Enigma Cipher, which was used for tactical messages, the Lorenz system encrypted teleprinter (teletype) transmissions and relied on a series of twelve rotors to generate pseudo-random key streams for each character.