The Start-Control-Connection-Reply is a PPTP control message sent in reply to a received Start-Control-Connection-Request message. This message contains a result code indicating the result of the control connection establishment attempt.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | PPTP Message Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Magic Cookie |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Control Message Type | Reserved0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol Version | Result Code | Error Code |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Framing Capability |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bearer Capability |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum Channels | Firmware Revision |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ Host Name (64 octets) +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ Vendor String (64 octets) +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
LengthTotal length in octets of this PPTP message, including the entire PPTP header.
PPTP Message Type1 for Control Message.
Magic Cookie0x1A2B3C4D.
Control Message Type2 for Start-Control-Connection-Reply.
Reserved0This field MUST be 0.
Protocol VersionThe version of the PPTP protocol that the sender wishes to use.
Result CodeIndicates the result of the command channel establishment attempt. Current valid Result Code values are:
1 - Successful channel establishment
2 - General error -- Error Code indicates the problem
3 - Command channel already exists;
4 - Requester is not authorized to establish a command channel
5 - The protocol version of the requester is not supported
Error CodeThis field is set to 0 unless a "General Error" exists, in which case Result Code is set to 2 and this field is set to the value corresponding to the general error condition as specified in Section 2.16.
Framing CapabilitiesA set of bits indicating the type of framing that the sender of this message can provide. The currently defined bit settings are:
1 - Asynchronous Framing supported
2 - Synchronous Framing supported.
Bearer CapabilitiesA set of bits indicating the bearer capabilities that the sender of this message can provide. The currently defined bit settings are:
1 - Analog access supported
2 - Digital access supported
Maximum ChannelsThe total number of individual PPP sessions this PAC can support. In a Start-Control-Connection-Reply issued by the PNS, this value SHOULD be set to 0 and it must be ignored by the PAC. The PNS MUST NOT use this value to try to track the remaining number of PPP sessions that the PAC will allow.
Firmware RevisionThis field contains the firmware revision number of the issuing PAC, or the version of the PNS PPTP driver if issued by the PNS.
Host NameA 64 octet field containing the DNS name of the issuing PAC or PNS. If less than 64 octets in length, the remainder of this field SHOULD be filled with octets of value 0.
Vendor NameA 64 octet field containing a vendor specific string describing the type of PAC being used, or the type of PNS software being used if this request is issued by the PNS. If less than 64 octets in length, the remainder of this field SHOULD be filled with octets of value 0.