问题
I am implementing Google Maps in my web application. Since Version 3 I don't need an API key for accessing their servers.
Google is limiting the requests, though.
How are they doing that? If external users are accessing my website, one map load is generated.
Do I have now about 25,000 map loads per IP address or how to they recognize my application?
回答1:
They probably use the location/domain of the current document(this detail will be sended to the Authentication-service).
But as long as it's not documented this may only be an assumption, you'll have to ask google how they do it.
来源：https://stackoverflow.com/questions/26378494/how-does-google-keep-track-of-map-loads-without-api-key