authentication token

(1) A USB key or app in a smartphone that provides a second authentication mechanism. See two-factor authentication.

(2) A security device given to authorized users in order to log in to a network. The security "token," "card" or "key" may be read like a credit card, or it may display a changing code that is typed in as the password or in addition to a primary password. Security codes generated in real time can also be created entirely in software as "soft tokens." USB drives that plug into the computer's USB port are also very popular as security tokens. See SecurID card, challenge/response, authentication and security protocol.

YubiKey Security Key

Yubico makes a variety of USB-based authentication tokens, including FIPS 140-2 validation. (Image courtesy of Yubico, www.yubico.com)