检测客户端是否在ASP.NET（MVC）中使用VPN连接

Question

Is there a way to detect if the client is using a VPN connection? I know that you can detect if he's using a proxy by using

GlobalProxySelection.Select

or

WebRequest.DefaultWebProxy

But those don't detect VPN. I'm building a website that uses geolocation and when clients uses VPN or Proxy I want to show a highlighted text saying that their location might not be correct because they're using any of those things.

Answer 1

If you have knowledge of the pool of IP addresses assigned to the VPN(s) you could monitor for those specific entries:

http://forums.asp.net/p/1356084/2782293.aspx