Re: [spring] Question about SRv6 Insert function

Suresh Krishnan <suresh.krishnan@gmail.com> Mon, 02 September 2019 16:07 UTC

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From: Suresh Krishnan <suresh.krishnan@gmail.com>
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Date: Mon, 2 Sep 2019 12:07:20 -0400
In-Reply-To: <3e31873a-278a-2154-0e71-4d820bba323d@gont.com.ar>
Cc: 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>
To: Fernando Gont <fernando@gont.com.ar>
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Subject: Re: [spring] Question about SRv6 Insert function
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Hi Fernando,

> On Aug 31, 2019, at 10:09 AM, Fernando Gont <fernando@gont.com.ar> wrote:
> 
> 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.

I have put down my thoughts on the future of header insertion work in a mail to the 6man list in May 2017. The mail can be found below

https://mailarchive.ietf.org/arch/msg/ipv6/4MevopH9_iQglUizhoT5Rl-TjRc <https://mailarchive.ietf.org/arch/msg/ipv6/4MevopH9_iQglUizhoT5Rl-TjRc>


> 
> 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.

Yes. If a draft violates RFC8200 and it hits the IESG for evaluation, I will certainly hold a DISCUSS position until the violations are fixed.

Thanks
Suresh