How the server knows the IP address?

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Hi,

In web programming, with the server variable REMOTE_ADDR, you can get the IP address of the user. For example in PHP:

PHP

<?php
echo $_SERVER['REMOTE_ADDR'];
?>

The output on the page is the IP address of the user.
But how the server knows the IP address of the user?

Thanks in advance.

Posted 30-Dec-12 23:32pm

Thomas Daniels

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Kalyan_A · Accepted Answer · 2012-12-30T23:47:00

Solution 1

Certain information about the user is always passed to the webserver when a connection is established. IP Address is one of them.

unless you are in a LAN, its usually the ip-address of the router that gets displayed when visiting public web sites.

hope that helps.

Cheers

Posted 30-Dec-12 23:47pm

Kalyan_A

Comments

Thomas Daniels 31-Dec-12 5:49am

Thank you!