YubiKey 5Ci Overview

The YubiKey 5Ci has six distinct applications, which are all independent of each other and can be used simultaneously.

Note: Some software such as GPG can lock the CCID USB interface, preventing another software from accessing applications that use that mode.

Interface

The YubiKey 5Ci uses a USB 2.0 interface. All of the applications are available through this interface.

Applications

FIDO2

The FIDO2 application allows for resident credentials to be stored and allows for password-less login on sites and devices that support it. The credentials can be protected with a PIN for convenient and strong two factor authentication. The FIDO2 application is FIDO certified.

USB Interface: FIDO

• More about FIDO 2
• Enhancements to FIDO 2 Support

OTP

The OTP applet contains two programmable slots, each can hold one of the following credentials:

• Yubico OTP
• HMAC-SHA1 Challenge-Response
• Static Password
• OATH-HOTP

USB Interface: OTP

U2F

The U2F application can hold an unlimited number of U2F credentials and is FIDO certified.

USB Interface: FIDO

OATH

The YubiKey 5 series can hold up to 32 OATH credentials and supports both OATH-TOTP (time based) and OATH-HOTP (counter based). Accessing this applet requires Yubico Authenticator.

USB Interface: CCID