Subject: [MSEC] GSAKMP Revisons

From: "Peter Lough" <[email-masked]>
Date: Mon, 11 Nov 2002 17:49:38 -0500

As noted previously, several changes are being made to GSAKMP incorporating the Original and Light protocols into one single document and dropping support for the original five message transaction.  This note will cover a few of the major areas of change in advance of the draft being available.

The Group ID field in the header was changed to a variable length field.  GSAKMP is designed to be used in IP v4 as well as IP v6 and other environments.  The size and format of the Group ID field was specific to IP v4.  Now, the Group Type used will dictate the size of the Group ID field.

Additionally, since this paper incorporates both GSAKMP and GSAKMP Light, but drops support for the original transaction, several items available in the tables throughout the document were no longer supported.  To reduce the requirements on any possible existing implementations, those fields that are no longer used will be marked as RESERVED.  For example, in GSAKMP Light Table 8: Exchange Types read:

Request to Join                     0
Invitation                               1
Invitation Response                2
Key Download                        3
Acknowledgement                  4
Rekey Event                          5
Group Removal/Destruction     6
No Message                          7
Light Request to Join              8
Light Key Download                9
Other                                    10-255

The same table is now represented in Table 8: Exchange Types as:

Reserved                              0 - 3
Notification                            4
Reserved                             5 - 6
No Message                          7
Light Request to Join             8
Light Key Download               9
Other                                   10 - 255

Note that type 4 "Acknowledgement" and "Notification" actually refer to the same message.  It has been renamed to more correctly indicate that it could be an ACK or a NACK.  Notification was the proper term.

The paper is currently under review and expected to be released in the near future.

Peter Lough
SPARTA, Inc.