Specify a URL that is accessible over the internet. This should be the entry point in networking infrastructure to proxy ...

Specify a URL that is accessible over the internet. This should be the entry point in networking infrastructure to proxy the call to the CSOM endpoint (_vti_bin/client.svc) of a site on an intranet SharePoint farm. Permissions on that site should be set to provide at least read permissions to all users who need to make calls over this connection.