Pomagajte oko SNMP

Code:
<!-- /*******************************************************************
 * Mikrotik SNMP signal reader by Perica Nikolic
 * Contact [email protected]
 * This copyright notice MUST stay intact for use.
 *
 * This is free software; you can redistribute it and/or modify.
 * This script is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
 * or FITNESS FOR A PARTICULAR PURPOSE.
 ********************************************************************/
 -->
<?php
// Date in the past
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");

// always modified
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
 
// HTTP/1.1
header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);

// HTTP/1.0
header("Pragma: no-cache");
?>
<html>
<head>
    <META HTTP-EQUIV="REFRESH" CONTENT="10">
    <link href="stil.css" type="text/css" rel="stylesheet" />    
</head>
<body>
<table align="center">
<caption class="maintable">Mikrotik signal list</caption>
<th class="maintable">MAC</th>
<th class="maintable">Signal <br>strenght(dBm)</th>
<?php


$ip="hostname or IP";    //Change IP to your host names, address
$mask_mac=false;        //Use to mask MAC adress (true / false );


$tx_bytes_snmp = snmpwalkoid("$ip", "public", ".1.3.6.1.4.1.14988.1.1.1.2.1.3");  

if (is_array($tx_bytes_snmp))

        while (list($indexOID,$rssi)= each($tx_bytes_snmp))
        {
            $oidarray=explode(".",$indexOID);
            $end_num=count($oidarray);
            $mac="";
            
            for ($counter=2;$counter<8;$counter++)
            {
                $temp=dechex($oidarray[$end_num-$counter]);
                if ($oidarray[$end_num-$counter]<16)
                        $temp="0".$temp;
                        
                if (($counter <5) and $mask_mac)
                    $mac=":"."xx".$mac;
                else 
                    if ($counter==7)
                        $mac=$temp.$mac;
                    else 
                        $mac=":".$temp.$mac;
            }
            
            
            $mac_oiu = substr(str_replace(":","-",$mac),0,8);
            $mac=strtoupper($mac);
            ?>
            <tr><td class="maincolum"><a href="http://standards.ieee.org/cgi-bin/ouisearch?<?php echo ($mac_oiu); ?>" target="_blank" class="tablelink"><?php echo ($mac); ?></a></td>
            <td class="maincolum" align="center"><?php echo ($rssi); ?></td>
            </tr>
            <?php                    
        }
    else 
    {
    ?>
    <tr><td colspan="2" class="warning">Please check SNMP settings and IP address</td></tr>    
    <?php    
    }
?>

</table>
</body>
</html>