Is there a name for the UX pattern where you enter a code from an unauthenticated device on an authenticated one in order to login?

Several services such as YouTube, Plex, and XFINITY use a pattern in which an unauthenticated device displays a code for the user to enter on an authenticated device. When the user enters the code on their authenticated device, their unauthenticated device is then authenticated.

Is there a name for this pattern? I'd love to learn more about best practices when implementing such a login system.

Here are a few screenshots of the process I'm talking about: