External redirects from your site trigger web-bots in different ways. If you want to hide them from the web-bots, and have all links on you site point internally, this script is a simple way to do so. You can either run it through a database, which makes

internalize.php

<?php
if(isset($_REQUEST['rd'])) {
    $new = $_REQUEST['rd'];
    // DB access
    include("db.php");
    $sql = "SELECT rdURL FROM rd WHERE rdName='".$new." LIMIT 1';";
    $result = mysql_query($sql);
    mysql_close($conn);
    if($result) {
        $row = mysql_fetch_array($result);
        $newURL = $row['rdURL'];
        header("Location: $newURL");
    }
    else {
        header("Location: home.php");
    }
}
header("Location: home.php");
?>