function ntohl($str)
{
    $res = unpack('I', pack('N', $str));
    return $res[1];
}
 
function htonl($str)
{
    $res = unpack('N', pack('I', $str));
    return $res[1];
}
 
function ntohs($str)
{
    $res = unpack('S', pack('n', $str));
    return $res[1];
}
 
function htons($str)
{
    $res = unpack('n', pack('S', $str));
    return $res[1];
}
 
function convert_integer(){
    $data = 2048;
    printf("Original: %s => Long  host byte order: %s, Network byte order: %s\n", $data, ntohl($data), htonl($data));
    echo "<br />";
    printf("Original: %s => Short  host byte order: %s, Network byte order: %s\n", $data, ntohs($data), htons($data));
}
 
convert_integer();