[spring] Understanding the replication draft

"Joel M. Halpern" <jmh@joelhalpern.com> Mon, 29 June 2020 22:17 UTC

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To: "spring@ietf.org" <spring@ietf.org>
From: "Joel M. Halpern" <jmh@joelhalpern.com>
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Date: Mon, 29 Jun 2020 18:17:36 -0400
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Subject: [spring] Understanding the replication draft
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I asked the authors a version of this question, but apparently my 
request got lost.

For now, this is speaking as an individual.  And I sincerely hope that I 
am merely missing something obvious.

I can not figure out from the current draft how the replication segment 
works in a SID (or label) stack.
Is there an unstated requirement that the segment must be the last one 
in the stack?
If not, how is a global SID after teh replication SID understood?
Or is a replication SID implicitly also a binding SID, replacing the 
rest of the stack no matter where it is in the stack?
    In which case it is implicitly effectively last?
Given taht a replication segment is qualified to a node, what happens if 
there is more than one in a stack?  Is it ignored when it hits a node it 
does not apply to?

Do I believe this can be made to work?  Yes.
But I can not understand how the WG could adopt the work with its 
current lack of clarity.
And this appears to me to be fundamental enough stuff that it can't be 
left to documents in other WGs.  It seems central to the definition and 
processing of replication SIDs.


Yours,
Joel - speaking as a participant