Comment by tallytarik
Comment by tallytarik a day ago
There are plenty of VPN and proxy detection services, either as a service (API) or downloadable database, which are surprisingly comprehensive. Disclaimer: I’ve run one since 2017. Years on, our primary data source is literally holding dozens of subscriptions to every commercial provider we can find, and enumerating the exit node IP addresses they use.
There are also other methods, like using zmap/zgrab to probe for servers that respond to VPN software handshakes, which can in theory be run against the entire IP space. (this also highlights non-commercial VPNs which are not generally the target of our detection, so we use this sparingly)
It will never cover every VPN or proxy in existence, but it gets pretty close.
> Years on, our primary data source is literally holding dozens of subscriptions to every commercial provider we can find, and enumerating the exit node IP addresses they use.
Assuming your VPN identification service operates commercially, I trust that you are in full compliance with all contractual agreements and Terms of Service for the services you utilize. Many of these agreements specifically prohibit commercial use, which could encompass the harvesting of exit node IP addresses and the subsequent sale of such information.