VPN (Virtual Private Network)
A VPN encrypts internet traffic and routes it through a remote server, masking the user's real IP address and location. VPNs are widely used for privacy, but also exploited to bypass geo-restrictions and evade detection.
What Is a VPN?
A Virtual Private Network (VPN) creates an encrypted tunnel between a user's device and a remote server operated by the VPN provider. All internet traffic passes through this tunnel, so websites and services see the VPN server's IP address instead of the user's real one. This provides two core benefits: privacy, because the user's ISP and local network cannot inspect the traffic, and location masking, because the exit IP can be in a different city or country.
Legitimate vs. Abusive Use
VPNs serve many legitimate purposes. Remote workers use them to access corporate networks securely. Journalists and activists in restrictive regions rely on VPNs to communicate safely. Everyday consumers use them to protect their data on public Wi-Fi networks.
However, bad actors also use VPNs to hide their identity while carrying out credential stuffing attacks, account takeovers, or multi-accounting schemes. Because VPN exit IPs are shared among many users, a single IP address can appear in both legitimate and malicious traffic, making simple IP blocking impractical.
How VPN Traffic Is Detected
Security teams identify VPN connections by maintaining databases of known VPN server IP ranges, analyzing network characteristics such as low latency from a supposedly distant location, and checking for mismatches between the claimed timezone and the IP's geolocation. More advanced approaches combine IP reputation scoring with device fingerprinting to assess risk without relying solely on the IP address.
VPN Detection with AntiProxies
AntiProxies maintains a continuously updated database of VPN, proxy, and Tor exit IP addresses. When a connection arrives, the API returns a risk score and connection-type classification so your application can make informed decisions, whether that means blocking, challenging with a CAPTCHA, or simply logging the event for review. For a technical deep dive into the methods used, see our blog post on how VPN detection actually works.