(1) See
one-time password.
(2) (
One
Time
Programmable) Entering data and instructions into the types of chips where they cannot be erased. See
PROM and
antifuse.
(2) (
One
Time
Pad) A cryptography method that uses a random number to generate a unique encryption key, which is stored on a smart card. See
SwapCrypt.
(3) (
Open
Trading
Protocol) A framework for Internet commerce that provides a consistent purchasing experience regardless of the hardware and software used.
(4) "On the phone." See
digispeak.