IP Address Verification

[fnbcprog]

What I am trying to put together is an application that allows office users only to create a username and password from a webpage. I want to add some added security to the site so that only people from within the office can create a username and password.

How do you verify that an IP Address is 192.168.x.xx? The first set must be the same as above but the last two digits may be different.

if ($IP_Address == "Some Verification Tool") {

 Let User Create Name;
}
else {

$IP_Address is not valid.

}

[jerdo]

if (ereg("^192\.168",$IP_ADDR))

[fnbcprog]

Thanks.

Do you know how to verify an email address?
It must [e-mail]

[hand]

<?
$dom   = "fcbn.net";
$check = explode("@","[e-mail]");
if ($check[1] != $dom) {
   print "sorry your domain is <i>$check[1]</i> instead of <i>$dom</i><br>\n";
}

or

<?
$email = "[e-mail]";

if (!preg_match("/^[_.0-9a-z-][e-mail]$/i", $email)) {
      print "sorry<br>\n";
}