Analyze VPN IPs to Prevent Masked Fraud Attempts

Many businesses have good reasons to detect VPNs: they don’t want their content stolen, they don’t want users accessing their sites from countries that block them, and they don’t want people using a VPN to do man-in-the-middle attacks on their public Wi-Fi. So, they’ve created detection tests that look for signs of VPN use and prevent site access by those who might be using a VPN for illegitimate purposes.

Analyze VPN IPs to prevent masked fraud attempts tests use various methods including traffic fingerprinting (which looks at the structure of data packets) and protocol or port analysis (which spots the presence of a VPN service by detecting changes in how the packets are formatted). Some also employ time zone mismatch detection, which identifies when web browser APIs return different time zones than those of the actual user’s device.

Proxy and VPN Detection for Secure Transactions: Stop Anonymous Threats

Another detection method is based on sniffing the network for VPN client devices and identifying their IP addresses from the DNS servers they resolve queries to. This requires a lot of computing power and can be extremely slow, but it’s effective at spotting VPN usage.

Other methods include deep packet inspection, which looks at network headers to identify VPN traffic by the presence of special flags or attributes. One final technique is called “port scanning,” which involves actively probing a device for open network ports that are used by VPNs and proxy services. This raises significant privacy concerns because it involves intrusive actions on a user’s device without their consent and can result in inaccurate detections (for example, when ports are configured for legitimate reasons like corporate network setups). All of these techniques work better in conjunction with others than on their own, but they are not foolproof.