Overview#

One-Time Password System (RFC 2289) describes a One-Time password authentication system ([OTP]).

The system provides authentication for system access (login) and other applications requiring authentication that is secure against passive attacks based on replaying captured reusable passwords.

One-Time Password System evolved from the S-KEY One-Time Password System that was released by Bellcore.

More Information#

There might be more information for this subject on one of the following:

• HMAC-based One-Time Password Algorithm
• One-Time password
• RFC 2289
• Universal Second Factor Challenges