RE: Adoption Call for "Improving the Robustness of Stateless Address Autoconfiguration (SLAAC) to Flash Renumbering Events"

["Pascal Thubert (pthubert)" <[e-mail]>]

Hello Bob:

I see 2 distinct parts in the draft. On the one hand, the draft describes a problem and the state of the IPv6 signaling, can and cannot do with the lifetimes in RAs. I believe that this is really useful to the community and can be a strong base to frame the solution.

Then the draft jumps to a proposition to solve the issue. I see controversy on the solution part because indeed there can be several ways to either signal the host that it should renumber or leave it to the host to figure that out quickly. 

I'll note that the host is impacted whatever; there are few major OSes but a great many brands of CPEs; that the host OS may be refreshed faster than CPEs, some of which are just plugged on the phone line till fiber shows up. This means a great many (failure) combinations and a very slow path to the problem globally solved if we need to change both sides. So a host-only change like Erik's variation of NUD makes a lot of sense to me. A policy recommendation to the ISPs to keep the prefix stable within the original advertised lifetime seems also like a good idea.

All in all, I believe that there should be several solution drafts proposed and then the group would decide what's the best approach.

My vote here is to split the doc to remove the solution piece and make that a separate draft; then adapt the problem statement and discuss the rest.

Keep safe,

Pascal

> -----Original Message-----
> From: ipv6 <[e-mail]> On Behalf Of Bob Hinden
> Sent: samedi 27 juin 2020 01:35
> To: IPv6 List <[e-mail]>
> Cc: Bob Hinden <[e-mail]>
> Subject: Adoption Call for "Improving the Robustness of Stateless Address
> Autoconfiguration (SLAAC) to Flash Renumbering Events"
> 
> This message starts a two week 6MAN call on adopting:
> 
>  Title:          Improving the Robustness of Stateless Address Autoconfiguration
> (SLAAC) to Flash Renumbering Events
>  Authors:        F. Gont, J. Zorz, R. Patterson
>  File Name:      draft-gont-6man-slaac-renum-08
>  Document date:  2020-05-18
> 
>  https://tools.ietf.org/html/draft-gont-6man-slaac-renum
> 
> as a working group item. Substantive comments and statements of support for
> adopting this document should be directed to the mailing list.  Editorial
> suggestions can be sent to the authors.  This adoption call will end on 10 July
> 2020.
> 
> There has been a lot of discussion on this draft, the chairs have some concerns
> with this document being adopted, but wanted the w.g. to express its opinion.
> Our concerns include:
> 
> This document proposes significant changes to SLAAC to fix what could be seen
> as an implementation problem in some edge routers.  This will affect all IPv6
> nodes, not only the ones communicating with these edge routers.  This part of
> IPv6 is a mature standard.   It is not clear we should modify all IPv6 hosts to
> deal with one corner case that may break other things allowed by the standard.
> 
> The changes proposed will make SLAAC more active, the changes include:
> 
>  o Reducing the default Valid Lifetime and Preferred Lifetime of PIOs  o Caps
> the received Valid Lifetime and Preferred Lifetime of PIOs.
>  o Frequent retransmission of configuration information  o Routers send all
> options in RA messages
> 
> Some additional questions for the w.g. to consider:
>  o Are there better approaches to address the underlying issue?
>  o Do the proposed changes work in all deployments?
>  o Are some proposed changes worth advancing even if the entirety may not
> be? If so, which ones?
> 
> We would like the w.g. to consider and comment on these issues when
> responding to this adoption call.
> 
> Bob & Ole
> 6man co-chairs