Disconnect PPTP Call Session

To disconnect a PPTP call session, the PNS MUST send a Call-Clear-Request message ([RFC2637] section 2.12) to the PAC, as specified in [RFC2637] section If no more call sessions exist with the PAC, the PNS SHOULD close the control connection with the PAC by sending the Stop-Control-Connection-Request message ([RFC2637] section 2.3) as specified in [RFC2637] section 3.1.1.