php code

<?php
    //from http://php.net/header
    header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
    header("Expires: Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past

    $random_number = rand(1,5);
    header( 'Location: https://website.com/network$random_number', true /* overwrite */, 303 );
?>