Re: [Sidrops] question on draft-ietf-sidrops-aspa-verification-04

"Guyunan (Yunan Gu, IP Technology Research Dept. NW)" <> Tue, 12 May 2020 07:12 UTC

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From: "Guyunan (Yunan Gu, IP Technology Research Dept. NW)" <>
To: Jay Borkenhagen <>
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Thread-Topic: [Sidrops] question on draft-ietf-sidrops-aspa-verification-04
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Date: Tue, 12 May 2020 07:11:58 +0000
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Subject: Re: [Sidrops] question on draft-ietf-sidrops-aspa-verification-04
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Hi Jay,

"mutual transit" sounds like a proper term to me and to be used here!


-----Original Message-----
From: Jay Borkenhagen [] 
Sent: Monday, May 11, 2020 10:13 PM
To: Guyunan (Yunan Gu, IP Technology Research Dept. NW) <>
Cc: SIDR Operations WG <>
Subject: Re: [Sidrops] question on draft-ietf-sidrops-aspa-verification-04

Guyunan (Yunan Gu, IP Technology Research Dept. NW) writes:

 > > And a final question about Section 7 Siblings (Complex Relations), regardless of the current description of what sibling relation is, do we think that sibling ASes are ASes that belong to the same operator? So any type of transition is free of charge?
 > Speaking about ASPA, we are speaking about peering relations, without any guess about the business between parties.
 > And from what I know - siblings are also spread among small networks, so this term is not strictly bound to the same administrative domain.
 > Yunan: well, I’m trying to understand what it means by “sibling”. Your draft defines how ASPA records are created for “sibling” relations, but no precise definition is given (only examples). I understand It is a complex relation, as stated in the draft, but still, I’m confused of the actual peering relations when we talk about “sibling”. Can you maybe provide a more specific text definition?

Hi Yunan,

I also find the term 'siblings' to be confusing and potentially misleading in the ASPA context, since it implies common parentage.  I believe that there is one and only one such 'complex relation' to be called out in ASPA verification, and that would be accurately described as 'mutual transit': ASes mutually agreeing to send prefixes received from each other to their peers and upstreams.

Would your request for clarification be met by the draft replacing its use of the term 'siblings' with 'mutual transit'?


						Jay B.