(PECL radius >= 1.1.0)
radius_send_request — Sends the request and waites for a reply
$radius_handle
   )After the Radius request has been constructed, it is sent by radius_send_request().
The radius_send_request() function sends the request and waits for a valid reply, retrying the defined servers in round-robin fashion as necessary.
   If a valid response is received, radius_send_request()
   returns the Radius code which specifies the type of the response. This will
   typically be RADIUS_ACCESS_ACCEPT,
   RADIUS_ACCESS_REJECT, or
   RADIUS_ACCESS_CHALLENGE. If no valid response is
   received, radius_send_request() returns FALSE.