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S/Key

S/Key definition

S/Key is a security authentication system that enhances the protection of user accounts and sensitive information. In the S/Key system, each password is used only once, providing an added layer of security against unauthorized access.

The S/Key authentication process begins with the generation of a master key or passphrase, which serves as the foundation for creating a series of one-time passwords. These passwords are derived from the master key using a cryptographic algorithm, ensuring that each password is unique and unpredictable.

See also: Secret key, Cryptographic key, Data key, Superkey

S/Key use cases

  • Remote Access. S/Key secures remote access by generating one-time passwords for authorized login.
  • Two-Factor Authentication (2FA). S/Key strengthens security by integrating one-time passwords as an extra layer alongside usernames and passwords.
  • High-Security Environments. With its one-time password system, S/Key mitigates government, defense, finance, and healthcare risks.
  • Online Banking and E-commerce. S/Key enhances security in financial transactions by requiring one-time passwords for authorized access.
  • Password Recovery. S/Key provides secure password recovery through temporary one-time passwords.