I'm using the vimeo PHP SDK, to fetch videos via the vimeo API. It works fine so far, except for one private video. A customer is trying to forbid the video to be played on any other domain, than the one he owns. Currently my code uses only the public scope, when fetching an access token. I'm getting an error for this specific video (video not found). What do I need to do, in order to fetch a video, which is whitelisted for a couple domains? Do I need to make an authenticated request? That would mean the user in the frontend has to log in on vimeo and I cannot simply fetch videos silently in the backend anymore?
"Authenticated Access Token" means the token is tied to your private data, and it can perform actions for you as though you were logged in.
You can use an authenticated token on a backend process to fetch your private videos (do not expose the token publicly, though).