HOTP
acronymsecuritycryptography
Stands for: HMAC-based One-Time Password
A one-time code advanced by a counter rather than a clock.
HMAC-based One-Time Password (RFC 4226) derives codes from a shared secret and an incrementing counter. TOTP is HOTP with the counter replaced by time; HOTP itself is used where a counter is easier to synchronize than a clock.
Also known as: hotp