Why is the length of transform ID 2 octets in IKEv2?

["Dondeti, Lakshminath" <ldondeti@nortelnetworks.com>]

Hi,

The length of the transform ID is 2 octets  in IKEv2 (was 2 octets in 
00, changed to 1 octet in 01, and back to 2 octets in 08 and stayed that 
way) whereas it is 1 octet in 2408.  I am curious about the reasoning 
behind the change(s).  Do we really need 2 octets for this field?

regards,
Lakshminath

Internet-Drafts@ietf.org wrote:

>A New Internet-Draft is available from the on-line Internet-Drafts directories.
>This draft is a work item of the IP Security Protocol Working Group of the IETF.
>
>	Title		: Internet Key Exchange (IKEv2) Protocol
>	Author(s)	: C. Kaufman
>	Filename	: draft-ietf-ipsec-ikev2-12.txt
>	Pages		: 102
>	Date		: 2004-1-7
>	
>This document describes version 2 of the Internet Key Exchange (IKE)
>protocol.  IKE is a component of IPsec used for performing mutual
>authentication and establishing and maintaining security
>associations.
>This version of the IKE specification combines the contents of what
>were previously separate documents, including ISAKMP (RFC 2408), IKE
>(RFC 2409), the Internet DOI (RFC 2407), NAT Traversal, Legacy
>authentication, and remote address acquisition.
>Version 2 of IKE does not interoperate with version 1, but it has
>enough of the header format in common that both versions can
>unambiguously run over the same UDP port.
>
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