How Can I Retrieve Connected Clients' MAC and IP Addresses Using PHP?

Retrieving MAC and IP Addresses of Connected Clients in PHP

In PHP, obtaining the MAC and IP addresses of connected clients requires different approaches due to varying availability of this information.

Server IP and MAC Addresses

The server's IP address is readily available through $_SERVER['SERVER_ADDR']. As for the MAC address, it can be retrieved by parsing the output of commands like netstat -ie (Linux) or ipconfig /all (Windows).

Client IP Address

The client's IP address can be obtained from $_SERVER['REMOTE_ADDR'].

Client MAC Address

Determining the client's MAC address in PHP is challenging, as it is generally not accessible to the server except when clients reside on the same Ethernet segment.

If clients reside on the same LAN, parsing the output of arp -n (Linux) or arp -a (Windows) can provide the MAC address. Here's an example in PHP using backticks:

<br>$ipAddress=$_SERVER['REMOTE_ADDR'];<br>$macAddr=false;</p>
<h1>run the external command, break output into lines</h1>
<p>$arp=arp -a $ipAddress;<br>$lines=explode("n", $arp);</p>
<h1>look for the output line describing our IP address</h1>
<p>foreach($lines as $line)<br>{<br>   $cols=preg_split('/s /', trim($line));<br>   if ($cols[0]==$ipAddress)<br>   {</p>
<div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false">   $macAddr=$cols[1];