Re: [spring] Comments on draft-geng-spring-sr-redundancy-protection

"Yangfan (IP Standard)" <> Mon, 17 May 2021 13:20 UTC

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From: "Yangfan (IP Standard)" <>
To: "Jeffrey (Zhaohui) Zhang" <>, 'Rishabh Parekh' <>
CC: "Gengxuesong (Geng Xuesong)" <>, "'Rishabh Parekh (riparekh)'" <>, "'Arvind Venkateswaran (arvvenka)'" <>, "''" <>
Thread-Topic: [spring] RE: Comments on draft-geng-spring-sr-redundancy-protection
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Date: Mon, 17 May 2021 13:20:16 +0000
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Subject: Re: [spring] Comments on draft-geng-spring-sr-redundancy-protection
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Hi Jeffrey,

To summarize the discussions a bit, I have two questions and hope to hear your comments and clarifications.
Q1: Are there any questions for clarifications or open issues with the current solution of redundancy-SID+Merging-SID+redundancy policy? If so, we would like to clarify them first.
Figure 1 in draft-geng-spring-sr-redundnacy-protection is the typical topology for Redundancy Protection in SR domain, as shown below.
Could you please explain how exactly Tree-SID solution is used in data plane for redundancy protection? For example, how the SR SID List is assigned, how the packet is encapsulated and forwarded from R1 to R2 in data plane, how Tree-SID and Replication SID are configured on network nodes, etc.
I don’t think I understand the entire forwarding flow correctly. In fact we are very interested in Tree-SID solution as it has been adopted as a WG work. It would be very helpful if you or anyone can provide a detailed illustration or comparison, for instance like the way of the Appendix in replication SID/Tree SID drafts.

Looking forward to your reply!