Re: [Lsr] Thoughts about PUAs - are we not over-engineering?

Robert Raszuk <robert@raszuk.net> Wed, 15 June 2022 13:41 UTC

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From: Robert Raszuk <robert@raszuk.net>
Date: Wed, 15 Jun 2022 15:41:12 +0200
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To: Peter Psenak <ppsenak@cisco.com>
Cc: Aijun Wang <wangaijun@tsinghua.org.cn>, "Van De Velde, Gunter (Nokia - BE/Antwerp)" <gunter.van_de_velde@nokia.com>, lsr <lsr@ietf.org>, draft-ppsenak-lsr-igp-ureach-prefix@ietf.org, draft-wang-lsr-prefix-unreachable@ietf.org
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Subject: Re: [Lsr] Thoughts about PUAs - are we not over-engineering?
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> Traffic will initially switch to alternate path, if any, an
> later the native mechanism (BGP signalling, tunnel keepalive, etc), will
> take over and bring it to its final state.
>

On one hand you are saying that UPA is useful where there is no BGP. So
let's talk about such a scenario.

Also not all tunnels have keepalives. I am talking about mGRE encapsulation
as an example where you simply encapsulate and have no idea other than
consulting RIB if the dst node is up or down.

In this discussed case it will keep sending packets to remote area only to
drop it there ... not good.

Thx,
R.