How can you tell if someone has a VPN?
No unencrypted packets If the Observer sees only encrypted packets and no unencrypted packets, it may be that a VPN is being used. While the world is rapidly moving towards encrypting as much data on the network as possible, there are still requests that are typically not encrypted.
Can you tell if IP is VPN?
The IP addresses of VPN servers are not difficult to recognize – there are even databases specialized in VPN detection that try to determine if an IP address belongs to a particular provider. This may interest you : How do I hide my IP address?. When you access a VPN-enabled website, it may be able to identify that you’re using a VPN based on your IP address.