Sending information to php page through plugin

[pianoman993]

Is it possible to send information to an external php through a plugin? I know that you can send information through the URL but that is not secure at all. Are there any other methods?! This is the code I have.

ob_start();

$_POST['username'] = $vbulletin->userinfo['username'];

include("http://mysite.com/custom_includes/manager.main.php? " . $_SERVER['QUERY_STRING']);
$get_manager = ob_get_contents();

ob_end_clean();

I am trying to send the username to my external php module through the plugin but no information is being received. Any and all help is greatly appreciated!!! Thank you!

- Pianoman993