Re: [spring] Alissa Cooper's Discuss on draft-ietf-spring-segment-routing-13: (with DISCUSS and COMMENT)

["Les Ginsberg (ginsberg)" <[e-mail]>]

Alissa -

I think I am properly understanding your question - but as you reference two non-existent sections in 
https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-07

<snip>
Section 5.2.2 of draft-ietf-6man-segment-routing-header...
...
Section 5.1.4 of draft-ietf-6man-segment-routing-header
<end snip>

I want to be sure.
Could you provide corrected references and/or the precise text which raises your concern?

Thanx.

    Les

> -----Original Message-----
> From: Alissa Cooper [mailto:[e-mail]]
> Sent: Wednesday, December 13, 2017 10:42 AM
> To: The IESG <[e-mail]>
> Cc: [e-mail]; [e-mail];
> [e-mail]; [e-mail]; [e-mail]
> Subject: Alissa Cooper's Discuss on draft-ietf-spring-segment-routing-13:
> (with DISCUSS and COMMENT)
> 
> Alissa Cooper has entered the following ballot position for
> draft-ietf-spring-segment-routing-13: Discuss
> 
> When responding, please keep the subject line intact and reply to all email
> addresses included in the To and CC lines. (Feel free to cut this introductory
> paragraph, however.)
> 
> 
> Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
> for more information about IESG DISCUSS and COMMENT positions.
> 
> 
> The document, along with other ballot positions, can be found here:
> https://datatracker.ietf.org/doc/draft-ietf-spring-segment-routing/
> 
> 
> 
> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
> 
> I ended up reading draft-ietf-6man-segment-routing-header in tandem with
> this document, and I have a question arising out of that. The trust model for
> SRv6 outlined in this document appears to be one of reliance on the fact that
> an SRH will only ever be inserted and appear within a single administrative
> domain.
> But Section 5.2.2 of draft-ietf-6man-segment-routing-header talks about an
> SRH being inserted by a device outside of the segment routing domain.
> Which is correct? I think this is an important question because the whole
> trust model for the SR information seems to rely on out-of-band trust
> between participating nodes.
> 
> I also think this is important because there is no discussion in this document
> of the impact of the inclusion of the SR metadata on the fingerprinting of the
> device that inserted it. Section 5.1.4 of draft-ietf-6man-segment-routing-
> header sort of alludes to this but seems to equate the capabilities of an
> active attacker (who can conduct a traceroute) with a passive attacker who
> could passively collect topology/fingerprinting information simply by
> observing SRHes flowing by on the network. If the limitation to a single
> administrative domain is meant to prevent such a passive attack (not sure if
> that is really true, but perhaps the document assumes it?), that's another
> reason that the existence of such a limitation needs to be clarified.
> 
> 
> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
> 
> 
> Per my DISCUSS comment, I think this document needs to include some
> considerations concerning the additional metadata that SRv6 adds to the
> packet.
> This has implications not just for passive observers but also for any node that
> logs the SRH.
>