Re: [mpls] Segment Routing vs. “Label Stacking” in draft-ietf-mpls-sfc-00

"Andrew G. Malis" <agmalis@gmail.com> Mon, 07 May 2018 11:16 UTC

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From: "Andrew G. Malis" <agmalis@gmail.com>
Date: Mon, 07 May 2018 08:15:47 -0300
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Subject: Re: [mpls] Segment Routing vs. “Label Stacking” in draft-ietf-mpls-sfc-00
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I just realized that I was a bit more terse in my email than I should have
been. When I said that the MPLS WG had never discussed “Label Stacking”,
well of course we have the label stack, but we had never discussed, prior
to Segment Routing, using the label stack as a method to do source routing
via only popping labels, with no label swapping along the path.

Cheers,
Andy


On Mon, May 7, 2018 at 8:05 AM, Andrew G. Malis <agmalis@gmail.com> wrote:

> The following URL is a diff between draft-farrel-mpls-sfc-04
> and draft-farrel-mpls-sfc-05, when section 6 was updated to change Segment
> Routing to “Label Stacking”. (Note that the only changes from
> draft-farrel-mpls-sfc-05 to draft-ietf-mpls-sfc-00 were the name and date
> change).
>
> https://tools.ietf.org/rfcdiff?url2=draft-farrel-mpls-sfc-05.txt
>
> If you examine the changes to section 6, it’s pretty clear (at least to
> me) that the changes are really just cosmetic in nature, such as removing a
> reference to draft-ietf-spring-segment-routing and changing a few terms
> here and there.
>
> That, combined with the fact that the MPLS WG had never discussed “Label
> Stacking” in a draft (never mind an RFC) prior to the introduction of
> Segment Routing leaves me to conclude that section 6 really does need to be
> removed in order to comply with the WG concerns about -04 and earlier
> revisions of draft-farrel.
>
> Thanks,
> Andy
>
>