[Home](./index.md) > [@digitalpersona/authentication](./authentication.md) > [TimeOtpAuth](./authentication.timeotpauth.md) ## TimeOtpAuth class Time-based one-time password (TOTP) authentication API. TOTP supports only authentication. Identification is not supported. Signature: ```typescript export declare class TimeOtpAuth extends Authenticator ``` ## Constructors | Constructor | Modifiers | Description | | --- | --- | --- | | [(constructor)(authService)](./authentication.timeotpauth.(constructor).md) | | Constructs a new TOTP authentication API object. | ## Methods | Method | Modifiers | Description | | --- | --- | --- | | [authenticate(identity, code)](./authentication.timeotpauth.authenticate.md) | | Authenticates the user using user's TOTP code. | | [getUnlockCode(userOrSerialNumber, challenge, token)](./authentication.timeotpauth.getunlockcode.md) | | Creates a code allowing to unlock a hardware TOTP device when it locks after a number of unsuccessful PIN entries. |