Re: [spring] SRv6 compression

Vasilenko Eduard <> Tue, 03 August 2021 10:49 UTC

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From: Vasilenko Eduard <>
To: Andrew Alston <>, "" <>, "" <>
Thread-Topic: [spring] SRv6 compression
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Subject: Re: [spring] SRv6 compression
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Hi all,
The number of people who could write the same as below but substitute “CRH” for “SRv6” is much bigger.
Because the number of SRv6 installations is much bigger.
If they would become proprietary then it would be even more harmful.
It is exactly the essence of this 2y old dilemma: Nobody sees a win-win solution.
Andrew, sorry, but you are not proposing it too. What you are proposing: the minority would win, the majority would lose.

I do not understand why this dispute still exists.
IMHO: it was decided by IETF at the time when SRH has been promoted to RFC 8754.
From that time, carriers chosen RFC believes that it is standard. It would be not fair to say to them now that IETF has changed the mind – RFC 8754 is a dead end.

Carriers that have chosen to implement personal draft (draft-bonica-6man-comp-rtg-hdr) were probably aware that it is a proprietary solution and may stay proprietary forever.

The problem could potentially hang indefinitely.
It would aggravate over time because more and more installations would diverge to incompatible solutions.
We are losing precious time. The more time – the more painful would be the decision.

Dear chairs,
If all augments are presented (I am not positive about it) then maybe voting?
For you to see who is the minority and who is the majority.
Not a good resolution for a technical dispute, but it is not purely technical, right?
Another possibility is to improve “convergence”: not to choose the final solution immediately, but cancel any current one from consideration then discuss only what is left.

PS: It is my personal opinion. I am far from the SRv6 team in Huawei.
Just this problem is so big for the community: 240 personal drafts stuck in the queue (in different WGs) waiting for NG data plane for SR over IPv6.
I could not imagine how big activity would start in the whole IETF after the data plane would be decided.
From: spring [] On Behalf Of Andrew Alston
Sent: Tuesday, August 3, 2021 9:13 AM
To: Qiuyuanxiang <>om>;; Henderickx, Wim (Nokia - BE/Antwerp) <>om>;
Subject: Re: [spring] SRv6 compression

From my side,

With or without the IETF – I will continue to use CRH and we will continue to make product choices based on it.  CRH is not SRv6 – it is, and we have stated this before, a building block for many things.

In our case – the ability to steer traffic is what drives a lot of what we do, but at the same time – the destination option SID for 16/32 bit which is an arbitrary number we can tie to functional behavior on the server side – is useful.

I also point out that as I said time and again, we could not wait for the IETF, and we have invested significantly in CRH development into various products – and the rejection of CRH by the IETF – by a DT inside SPRING when the document is actually in 6man and is not srv6 – will simply lead to a case of us making large purchasing decisions on the vendors that choose to support what would be a proprietary protocol.  So – rather than contributing to open standards the IETF by choosing one option – an option favored in the DT report – where 5 outta 7 members were actually authors or directly related to CSID – the IETF will be contributing towards what will become a proprietary protocol – either on IANA allocated code points, experimental code points or squatted code points – either way – CRH will continue and we will base our millions a year in purchasing partially on this factor (especially considering the significant amount of development resource that has been put into this – and yes – people will say – why did you put the resources into it – well – CRH has been stable in RFC since before CSID existed – and development cannot stop because of inertia in the IETF)

CRH is functional – in production – and deployed – and caters for use cases simply not covered by CSID – because they have entirely different purposes.  CSID was built to compress SRv6 – CRH is a building block for whatever the hell you want it to be.  To choose one over the other disregards this entirely.

Hence, I say this again, I am supportive of moving multiple options forward here – one within spring, and the other in 6man where it currently resides, to cater for disparate use cases.



From: spring <<>> On Behalf Of Qiuyuanxiang
Sent: Monday, August 2, 2021 1:01 PM
To:<>; Henderickx, Wim (Nokia - BE/Antwerp) <<>>;<>
Subject: Re: [spring] SRv6 compression


As a vendor, we do hope to pick one solution to be standardized, to facilitate the network deployment.
Also, since the CSID has been implemented by many vendors, I will suggest to adopt CSID.

Best Regards,
Yuanxiang Qiu

发件人: spring [] 代表<>
发送时间: 2021年7月31日 16:38
收件人: Henderickx, Wim (Nokia - BE/Antwerp) <<>>;<>
主题: Re: [spring] SRv6 compression

Agree. Picking 1 solution to satisfy our requirements will benefit both the vendors and the operators.

Best Regards,
Zhenqiang Li

From: Henderickx, Wim (Nokia - BE/Antwerp)<>
Date: 2021-07-27 15:11
Subject: [spring] SRv6 compression
Given the design team accomplished the work on providing requirements and analysis to compress an SRv6 SID list, I would recommend we pick 1 solution similar to what was done in NVO3 (when we discussed GENEVE, GUE, GPE, etc) given this has to be implemented in HW..

I hope we can conclude on this asap and move forward on this topic

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