[1] mod_remoteip - Apache HTTP Server ( (1/9/2012, 6:11:16 PM 版)) <http://httpd.apache.org/docs/2.3/mod/mod_remoteip.html>
[2] draft-stecher-icap-subid-00 - ICAP Extensions ( (8/31/2014, 8:09:58 AM 版)) <http://tools.ietf.org/html/draft-stecher-icap-subid-00#section-3>
Google search: X-Client-IP: