1、通过header、端口反扫来识别,见proxyserverprivacy的说明:
As you already know Basis proxy detector analyze typical proxy variables that your browser send to the web server, among other things, VIA, PROXY_CONNECTION and X_FOWARDED_FOR and can succesfuly determine of you are behind transparent proxy or anonymous proxy. Elite proxy (Level 1 and Level 2 proxy defined by ProxyJudge) does not sends out HTTP requests that include any of the three afore mentioned HTTP headers). Proxy checker can with success check and identify Elite proxy. And not only Elite proxy but also free web proxy server including any kind of CGI proxy or php proxy)
That's because Advanced Proxy Detector try to examine and analyze not only typical proxy headers in HTTP request but also common proxy port (8080,80,6588,8000,3128,553,554).
2、通过服务反扫:
http://whatismyipaddress.com/proxy-check
IP | 1.1.1.1 |
rDNS | FALSE |
WIMIA Test | FALSE |
Tor Test | FALSE |
Loc Test | FALSE |
Header Test | FALSE |
DNSBL Test | FALSE |
3、其他特征
ip归属地时区与browser端的时区差异
ip归属地语言与browser端的语言差异
是否是mail server
是否是hostname