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RC4

(also Ron's Code 4)

RC4 definition

RC4 is a stream cipher. The name Rivest Cipher 4 comes from its creator Ron Rivest. He designed RC4 back in 1987 in order to simplify software implementations. RC4 was used in various cybersecurity applications since this symmetric stream cipher algorithm favored encryption. RC4 operates on data stream by stream to encrypt multiple pieces of information. Back in the day, it was an efficient way to encrypt data. However, as technology was advancing fast, its usage has diminished. Furthermore, many vulnerabilities were discovered in its key-scheduling algorithm.

See also: encrypted file transfer, creepware

Key RC4 applications

  • File encryption: Rivest Cipher 4 has been used for secure sensitive data and file encryption.
  • Cryptographic protocols: RC4 was utilized in different applications and cryptographic protocols as a stream cipher.
  • Secure communications: RC4 has been employed in various secure communication systems and applications in the past, such as VPNs (Virtual Private Networks) and other secure messaging networks.
  • Wireless security: Before AES encryption (Advanced Encryption Standard), RC4 was used in Wi-Fi encryption protocols, such as WEP and WPA (Wi-Fi Protected Access).
  • SSL and TLS: RC4 was used in secure socket layer and transport layer security protocols to support secure web communications by encrypting data.