ip login script

[techker]

hey guys i got this code but i need to add a code that you can't signup with the same ip?
in my signup form.

[code]<?php
// ip_grab.php
/* Note: You can also check against $_SERVER variables
  not included in this script */
function ipGrabber() {
    if(getenv('HTTP_CLIENT_IP')):
        $ip = getenv('HTTP_CLIENT_IP');
    elseif(getenv('HTTP_X_FORWARDED_FOR')):
        $ip = getenv('HTTP_X_FORWARDED_FOR');
    else:
        $ip = getenv('REMOTE_ADDR');
    endif;
    return $ip;
}   

echo '<p>Your IP is: <b>'. ipGrabber() .'</b>.</p>';
?>[/code]

thx for the help

[chiprivers]

Your assuming that people have fixed ip?

[techker]

good question..i juste don't want the members to login from any where?and track there ips.

[Jessica]

What? You don't want your members to be able to login from anywhere? That seems kind of restrictive.

IP tracking is a very poor method for tracking users. There are many ways to change or mask your IP address.

[ted_chou12]

really? how do you change your ip address? I thought it is hard to modify thats why online services detect your ip for multiple registerations!
Ted

[Jessica]

There are dynamic IPs, and you can also just request your IP to be changed.
You can also use masking services and proxies.

It can help when trying to detect multiple users, but it's not very accurate. My husband and I are both on several sites, and we use the same IP. We use different emails and names, so we are not the same person. Allow people to use the same IP, and simply record it to help determine if it might be the same person.

For example - someone registered on my site once with two different emails, which were similar, and the same IP. Now, it could have been two different people - but they used the same birthdate and password - that was why I figured it was the same person.

[ted_chou12]

okay, I think I understand a bit... 8) but not much  :-\. How big does an ip address cover, like a street? a house? or what?
Thanks for the knowledge
Ted.

[Jessica]

http://en.wikipedia.org/wiki/IP_address

An IP address (Internet Protocol address) is a unique address that devices use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard (IP)—in simpler terms, a computer address. Any participating network device—including routers, computers, time-servers, printers, Internet fax machines, and some telephones—can have their own unique address. Also, many people can find personal information through IP addresses.

An IP address can also be thought of as the equivalent of a street address or a phone number (compare: VoIP(voice over (the) internet protocol)) for a computer or other network device on the Internet. Just as each street address and phone number uniquely identifies a building or telephone, an IP address can uniquely identify a specific computer or other network device on a network.

An IP address can appear to be shared by multiple client devices either because they are part of a shared hosting web server environment or because a proxy server (e.g., an ISP or anonymizer service) acts as an intermediary agent on behalf of its customers, in which case the real originating IP addresses might be hidden from the server receiving a request. The analogy to telephone systems would be the use of predial numbers (proxy) and extensions (shared).

[ted_chou12]

sounds very technical... :)

[trq]

To put it another way. At the place where I work we have around 700 pcs all connected to the internet. To your website, anyone logging in from any of these pcs would like like the same person. Each pc has its own internal ip address used on our LAN, but we all share 1 ip address for the internet WAN.