The MPLS WG Archive

[David Charlap <David.Charlap@marconi.com>]

Ganesh Murugesan wrote:
> 
> I had a minor question (more on the wording) in
> draft-ietf-mpls-rsvp-lsp-tunnel-09.txt on RROs.
> 
> The draft on Page 33 says
>         The contents of a RECORD_ROUTE object are a series of
> variable-length data items called subobjects. Each subobject has its
> own Length field. The length contains the total length of the
> subobject in bytes, including the Type and Length fields. The length
> MUST always be a multiple of 4, and at least 4.
> Since the three types of subobjects defined under RRO are the IPv4,
> IPv6 and the label recording subobjects, shouldn't the last line say
> strictly greater than 4, since all the three types have length
> greater than 4.

There have been ERO/RRO subobjects in prior drafts (now expired) that
were length 4 (the "LSP Termination" subobject, which was deleted fron
the draft in version -05).

It is possible that we may define subobjects of length 4 in the future
as well.

What purpose is served by changing the wording so that we are no longer
free to define a new subobject of length 4?

-- David