AUTHENTICATION SYSTEM(S) WITH MULTIPLE AUTHENTICATION MODES USING ONE-TIME PASSWORDS OF INCREASED SECURITY

Authentication processing is provided which includes generating an authentication parameter as a function of a time-dependent input using a predetermined transformation having an inverse transformation. Multiple authentication modes are supported, with a bit-length of the time-dependent input of one authentication mode being different from a bit-length of the time-dependent input of another authentication mode. Generating the authentication parameter is dependent, in part, on whether the time-dependent input is of the one authentication mode or the other authentication mode. A time-dependent password including a character string is generated from the authentication parameter using another predetermined transformation having another inverse transformation. The time-dependent password is forwarded within the authentication system for authentication by an authenticator.