Re: [Lsr] Prefix Unreachable Announcement Use Cases

Gyan Mishra <> Sun, 15 November 2020 20:01 UTC

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From: Gyan Mishra <>
Date: Sun, 15 Nov 2020 15:01:13 -0500
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To: Robert Raszuk <>
Cc: "Acee Lindem (acee)" <>, Aijun Wang <>, lsr <>
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Subject: Re: [Lsr] Prefix Unreachable Announcement Use Cases
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Robert & Acee

I have been working with Aijun to help clean up the verbiage in the draft
which after IETF 109 will plan to do an update based on feedback.

I will be presenting this draft as well as the passive interface draft
tomorrow morning.

It has been challenging trying to graphically depict Aijun’s goals and
intentions but I have tried my best to do so in the presentation tomorrow

Kind Regards


On Sun, Nov 15, 2020 at 11:44 AM Robert Raszuk <> wrote:

> Hi Aijun,
> I would in fact only propose that the presented mechanism is narrowed down
> to invalidate BGP (service) routes - in fact their next hops.
> The reason being that the moment you make the solution generic, moreover
> the moment you want it to be used in RIB and data plane I am afraid you are
> running into similar (even if local) deaggregation mechanism like recently
> described in RIFT. That would kill all the scalability of advertising
> summary routes in the first place and I bet would face lots of opposition.
> Thx,
> R.
>> I would actually trim most use cases leaving just one - to signal remote
>> service node (ex: PE) going down in the presence of summary route being
>> advertised from remote area or pop.
>>  [WAJ] Yes, this may be the most useful use case, but the PUA mechanism
> can also apply to other scenarios. We want to make it one general solution.
> _______________________________________________
> Lsr mailing list


*Gyan Mishra*

*Network Solutions A**rchitect *

*M 301 502-134713101 Columbia Pike *Silver Spring, MD