Authentication using a conversational user interface

A method comprising:

• receiving an open credential from a user;
• determining, based on the open credential, an address of a personal communication device of the user;
• sending a one-time passphrase transmitted from an authentication system to the address of the personal communication device, the one-time passphrase comprising common but incongruous words;
• prompting the user to verbalize the one-time passphrase to a processor-implemented, conversational user interface;
• receiving, by the conversational user interface, utterances from the user and communicating the utterances from the conversational user interface to the authentication system via a trusted communication channel;
• determining, by the authentication system using speech recognition, the presence or non-presence of the one-time passphrase within the received utterances;
• authenticating, by the authentication system, the user in response to detecting the presence of the one-time passphrase within the received utterances;
• after authenticating the user, storing change commands involving protected resources in response to verbal input by the user;
• prior to executing the stored change commands:
• prompting the user to verbalize a second one-time passphrase to the conversational user interface via the personal communication device;
• determining, by the authentication system using speech recognition, presence or non-presence of the second one-time passphrase within second utterances communicated from the conversational user interface to the authentication system;
• and
• re-authenticating the user in response to detecting presence of the second one-time passphrase within the second utterances;
• and
• executing the stored change commands in response to successfully re-authenticating the user.

A system comprising:

• an authentication system operable to:
• receive an open credential from a user of the system;
• determine, based on the open credential, an address of a personal communication device of the user;
• transmit a one-time passphrase to the address of the personal communication device, the personal communication device prompting the user to verbalize the one-time passphrase;
• and
• a processor-implemented, conversational user interface operable to:
• receive utterances from the user in response to the prompting;
• and
• communicate the received utterances to the authentication system;
• wherein the authentication system is operable to:
• determine, using speech recognition, presence or non-presence of the one-time passphrase within the received utterances;
• authenticate the user to a session in response to detecting presence of the one-time passphrase within the received utterances;
• and
• during the session, re-authenticate the user by:
• prompting the user to provide subsequent utterances, which include a subsequent one-time passphrase different from the one-time passphrase;
• and
• determining presence or non-presence of the subsequent one-time passphrase within the subsequent utterances.