There are perhaps hundreds if not thousands of articles on obtaining your visitor’s IP address. The majority if these entries will refer to a small subset of global $_SERVER variables (HTTP_X_FORWARDED_FOR, HTTP_CLIENT_IP, and REMOTE_ADDR). Although both fast and simple solutions utilizing nested ternary operations exist, they are generally prone to a fairly large bug. The HTTP_X_FORWARDED_FOR server directive may contain a comma delimited list of IP addresses based upon several proxy hops prior to the client request packet reaching it’s destination.
After scouring the web I came across two sites demonstrating what appears to be the most accurate IP retrieval method I have come across. I found a number of inefficiencies in the two functions so I’m going to provide you with my optimized version. more »
