FWIW that is a really old spec. The FIDO 2.0 Bluetooth transport is described at: https://fidoalliance.org/specs/fido-v2.0-rd-20180702/fido-client-to-authentica

FWIW that is a really old spec. The FIDO 2.0 Bluetooth transport is described at: https://fidoalliance.org/specs/fido-v2.0-rd-20180702/fido-client-to-authenticator-protocol-v2.0-rd-20180702.html#ble https://fidoalliance.org/specs/fido-v2.0-rd-20180702/fido-cl... But an article from VentureBeat[0] mentioned it's a new transport called 'cloud assisted Bluetooth Low Energy' or caBLE, which they've submitted to FIDO for standardization. [0]: https://venturebeat.com/2019/04/10/you-can-now-use-your-android-phone-as-a-2fa-security-key-for-google-accounts/ https://venturebeat.com/2019/04/10/you-can-now-use-your-andr...