Why is a one-time password safe? The OTP feature prevents some forms of identity theft by making sure that a captured user name/password pair cannot be used a second time. Typically the user's login name stays the same, and the one-time password changes with each login.

Why is OTP used?

OTP, One Time Passwords in full, can be sent to the user's phone via SMS, Voice or Push message and is used to protect web-based services, private credentials, and data. OTP's will minimize the risk of fraudulent login attempts and thus the risk of stolen data. ... This 'something' can be the user's phone.

How do OTPs work?

A lockstep synchronized OTP is one that generates new, temporary passwords based on a previous OTP. Your OTP device uses a seed code and a hash chain to generate OTPs first from the seed code and then from every subsequently used OTP. These are commonly known as HOTP, or HMAC-based One-time Password.