PHP port Scanner

<?php


$host = $_POST['host'];
$start = $_POST['start'];
$end = $_POST['end'];
$proto = $_POST['protocol'];
$serv = $_POST['services'];

// Start table
?>
<div align="center">
<div align="center">
<div align="center">
<div align="center">
<div align="left">
<div align="center"><img src="http://img190.imageshack.us/img190/2239/sloganleft.png" alt="" width="305" height="130" />
  <table width='300' border='0' cellspacing='0' cellpadding='0'>
    <tr>
      <td>Host name or IP:</td>
      <td><input type='text' name='host' value='<?php echo $host; ?>' /></td>
    </tr>
    <tr>
      <td>Starting Port:</td>
      <td><input type='text' name='start' value='<?php echo $start; ?>' /></td>
      </tr>
    <tr>
      <td>Ending Port:</td>
      <td><input type='text' name='end' value='<?php echo $end; ?>' /></td>
      </tr>
    <tr>
      <td>Protocol:</td>
      <td>
        <select name='protocol'>
          <option value='tcp'>tcp</option>
          <option value='udp'>udp</option>
        </select>
      </td>
      </tr>
    <tr>
      <td>Show services:</td>
      <td><input name='services' type='checkbox' value='yes' /></td>
      </tr>
    <tr>
      <td colspan='2'><input type='submit' value='Scan Ports' /></td>
      </tr>
  </table>
  <br /><br />
  <?php
// End table


if(isset($host) && isset($start) && isset($end) && isset($proto))
{
echo "<strong>Results:</strong><br />";

for($current = $start; $current <= $end; $current++)
{
if($serv == "yes")
{
$service = getservbyport($current, $proto);
}

// Try to connect to port
$result = fsockopen($host, $current, $errno, $errstr, 1);

// Show results
if($serv == "yes")
{
echo "Port: <strong>".$current."</strong> is commonly used for: <strong>".$service."</strong> and was ";
}
else
{
echo "Port: <strong>".$current."</strong> was ";
} 
if($result)
{
echo "<font color='green'><strong>OPEN</strong></font><br />";
}

else
{
echo "<font color='red'><strong>CLOSED</strong></font><br />";
}

}
}
?>