Re: [spring] Question about SRv6 Insert function

Fernando Gont <fernando@gont.com.ar> Sat, 31 August 2019 14:10 UTC

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To: Ron Bonica <rbonica=40juniper.net@dmarc.ietf.org>, li zhenqiang <li_zhenqiang@hotmail.com>, draft-voyer-6man-extension-header-insertion <draft-voyer-6man-extension-header-insertion@ietf.org>, draft-ietf-spring-srv6-network-programming <draft-ietf-spring-srv6-network-programming@ietf.org>, "6man@ietf.org" <6man@ietf.org>, "spring@ietf.org" <spring@ietf.org>
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From: Fernando Gont <fernando@gont.com.ar>
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Subject: Re: [spring] Question about SRv6 Insert function
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On 30/8/19 20:24, Ron Bonica wrote:
> Li,
> 
>  
> 
> In the scenarios that you mention, below, SRv6 nodes have the following
> options:
> 
>  
> 
>  1. To prepend and IPv6 header, with its own SRH
>  2. To insert an SRH, as described below
> 
>  
> 
> Option 1 is in keeping with the word and spirit of RFC 8200. As you
> point out, Option 2 contradicts RFC 8200.
> 
>  
> 
> So, we should probably explore the motivation for Option 2). If the
> motivation is not sufficient, we should probably standardize on Option 1.

My argument would be:
Folks would do whatever they please with 1). If somehow they feel the
need to do 2), they should *refrain from even suggesting it*, post an
internet draft that proposes to update RFC8200 to allow for the
insertion of EHs, wait for that to be adopted and published, and only
then suggest to do EH insertion.

P.S.: Given the amount of discussion there has been on this topic in the
context of RFC8200, I'd like to hope that there's no draft-ietf document
suggesting EH-insertion or, if there is, the relevant ADs and chairs
make sure that's not the case anymore.

Thanks!

Cheers,
-- 
Fernando Gont
e-mail: fernando@gont.com.ar || fgont@si6networks.com
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