Review: TeleSign 2FA

TeleSign 2FA is a full API and SDK that allows an enterprise to integrate two-factor authentication into its existing web applications. It allows administrators to modify their existing web applications to include a drop-down box on the authentication screen from which a user can choose the way of receiving their one-time passcode. Passcodes can be sent to the user either via SMS text message or by phone to a number that has been previously registered. This provides full out-of-band two-factor authentication without the need to purchase additional tokens.