If AMP is federated, that's a lot less disturbing to me than my first impression.
If AMP is federated, that's a lot less disturbing to me than my first impression.
Anyone can cache a signed exchange from anyone else. So, for example if you went and fetched a signed exchange from https://amppackageexample.com/ (or any other site that supports one, this is just an example), you could then serve that from your own server, more or less just like any other file (the less is that you need to set the right Content-Type header, but it otherwise works just like serving an image or a zip file).
Then, if a user visited the URL on your site https://yoursite.com/cached-copy-of-amppackageexample.com/ then the browser would display https://amppackageexample.com/ in the URL bar, as though that URL had 301 redirected, but without the extra network fetch.
Google search does exactly this, just loading a cached copy of the Signed Exchange, and any other cache (or even any website) can do the same.
So, if you publish a signed exchange, you are allowing all caches to do this, not just a selected cache. However, since the document is signed, absolutely no caches can modify the document or the browser will reject it and error handle (typically just making an actual redirect to your domain).
I hope that helps to understand.
In short, only being in Google's AMP cache gets you good rankings on Google Search.
Bing also hosts an AMP Cache if that's of interest to you.
AMP is federated. Anybody who wants instant loading of AMP pages linked from their own pages can run their own AMP cache, as Bing and Baidu (among others) do.
> If you use a different AMP cache than Google's, does it affect your search ranking/carousel positioning with them?
Bing and Baidu running their own AMP caches doesn't affect their Google ranking. Why would it?