WPT not detecting CDN being used

[pmeenan]

I'm seeing 250ms+ ping times to srv-live.lazada.co.id from the US. Is that actually on a CDN with distributed edge nodes? WPT doesn't "Grade" the CDN because it may not make sense for all sites but I do want it to accurately reflect if the content is being edge-served from a global (or at least distributed for the market) platform.

An "X-CDN" header would let anyone arbitrarily spoof the results to make it look like it is being served from a CDN even if it isn't. That wouldn't be a problem if the site owner is doing it because it makes them feel better but if it is being done by a 3rd-party for included snippets or something like that then that would be fooling the site owner into thinking the content is actually coming from a CDN when it isn't.

Granted, the current logic can be tricked if you really wanted to but I'd rather not encourage that behavior. If you see cases where an actual CDN is not being detected then I'd be happy to fix the logic but I'm not really interested in labeling things as a CDN that aren't.