I wonder if someone would be able to offer some advice on how to alter the code snippet below to ban ip ranges or could come up with something that will work because I run an alcohol and drug recovery resource site which has recently been listed on a number of search engines and we have started to attract regular abusive users that disrupt the site and affect other members.

<?php

$ip = getenv("REMOTE_ADDR");
switch ($REMOTE_ADDR)
{
case "xxx.xx.xx.xx";
Header("Location: blocked.php");
break;

}
?>

I have found this will redirect a user to a page explaining that they have been denied access to the site but as soon as they disconnect and reconnect to their isp their ip number changes so I have to keep tracking trouble makers rather than spending time with our members.

If anyone can help me I would be very very grateful.