Original text:
user authentication using asymmetric cryptography that can be invoked from a web browser or native client.  Version 2.2 of the FIDO Client to Authenticator Protocol (CTAP) supports a new cross-device <del> authentication protocol, called "hybrid", which enables an external device, such as a phone or tablet, to be used as a roaming </del>  authenticator for signing into the primary device, such as a personal computer.  This is commonly called FIDO Cross-Device Authentication <del> (CDA). </del>  When a user wants to authenticate using their mobile device (authenticator) for the first time, they need to link their authenticator to their main device.  This is done using a scan of a QR code.  When the authenticator scans the QR code, the device sends an encrypted BLE advertisement containing keying material and a <del> tunnel ID.  The main device and authenticator both establish connections to the web service, and the normal CTAP protocol exchange occurs. </del>  If the user chooses to keep their authenticator linked with the main device, the QR code link step is not necessary for subsequent use.

Reviewer comments:
Addresses issue NAME
From WGLC Current text: "supports a new cross-device authentication protocol, called "hybrid"" Proposed text: "supports a new cross-device transport protocol, called "hybrid transports" Propose adding the following at the end of the first paragraph: "CTAP 2.2 hybrid transports is implemented by the client and authenticator platforms." Current text: "The main device and authenticator" Proposed text: "The main device (CTAP client) and authenticator" Current text: "The user will receive a push notification on the authenticator." Proposed text: "The user will typically receive a push notification on the device serving as the FIDO authenticator." Current text: "Both the Consumption Device and the authenticator require BLE support." Proposed text: "Both the Consumption Device and the authenticator require BLE support and also need access to the internet" s/hybrid transport/hybrid transports Current text: "The mobile phone must support CTAP 2.2+ to be used as a cross-device authenticator." Proposed text: "The device serving as the FIDO authenticator must support CTAP 2.2+ to be used as a cross-device authenticator." see: URL NAME

Revised text:
user authentication using asymmetric cryptography that can be invoked from a web browser or native client.  Version 2.2 of the FIDO Client to Authenticator Protocol (CTAP) supports a new cross-device  <ins> authentication protocol, called "hybrid transports", which enables an external device, such as a phone or tablet, to be used as a roaming </ins> authenticator for signing into the primary device, such as a personal computer.  This is commonly called FIDO Cross-Device Authentication  <ins> (CDA).  CTAP 2.2 hybrid transports is implemented by the client and authenticator platforms. </ins> When a user wants to authenticate using their mobile device (authenticator) for the first time, they need to link their authenticator to their main device.  This is done using a scan of a QR code.  When the authenticator scans the QR code, the device sends an encrypted BLE advertisement containing keying material and a  <ins> tunnel ID.  The main device (CTAP client) and authenticator both establish connections to the web service, and the normal CTAP protocol exchange occurs. </ins> If the user chooses to keep their authenticator linked with the main device, the QR code link step is not necessary for subsequent use.