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All IPs used by Google have PTR records to the 1e100.net zone so it is straightforward to determine whether any given domain is a Google domain. e.g. googlevid
by quaker5567 8y ago
All IPs used by Google have PTR records to the 1e100.net zone so it is straightforward to determine whether any given domain is a Google domain.
e.g. googlevideo.com resolves to 172.217.4.196 and the PTR for that IP is lga15s48-in-f196.1e100.net
They even have a faq for this: https://support.google.com/faqs/answer/174717?hl=en https://support.google.com/faqs/answer/174717?hl=en