Identify VPN Users With IP Address Analysis

Many users connect to the Internet via VPNs or proxies, which can be used to bypass geographic restrictions. As a result, businesses and websites that rely on the revenue generated by traffic from those users may need to detect those VPN connections to block access.

Identify VPN users with IP address analysis is challenging, as VPNs and proxies often use non-standard ports to conceal their presence, and they employ a variety of obfuscation techniques to avoid detection. However, some techniques can help to identify VPN users, including scanning for open ports associated with VPN protocols; comparing the timezone reported by the user’s web browser against the timezone of the VPN exit node; and examining the ownership information of an IP address using whois databases.

Perform an IP Lookup to Reveal Location and Risk Data

The most advanced detection method for identifying VPN and proxy users is deep packet inspection (DPI), which involves the use of complex software to analyze data packets. Typically deployed at ISPs and local networks, DPI is able to recognize patterns that suggest a user is connecting through a VPN or proxy server.

While DPI is more effective at detecting VPN and proxy users, it is not without drawbacks that can limit its application. For example, DPI requires the deployment of hardware or software at a scale that makes it impractical for many business sites to implement. And in some cases, DPI can produce false positives, identifying genuine VPN users who have legitimately chosen to use a service for privacy or security reasons.