[Roll] processing of multiple SRH-6LoRH

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 22 April 2016 13:48 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
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Date: Fri, 22 Apr 2016 09:48:40 -0400
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Subject: [Roll] processing of multiple SRH-6LoRH
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section 5.5 of routing-dispatch says:

   Else (meaning that this is the last entry in the SRH-6LoRH header),
      and if there is no next SRH-6LoRH header after this then the SRH-
      6LoRH is removed.

Fair enough.

   Else, if there is a next SRH-6LoRH of a Type with a larger or equal
      value, meaning a same or lesser compression yielding same or larger
      compressed forms, then the SRH-6LoRH is removed.

okay, so when the new SRH provides more bytes, we remove the consumed one.

   Else, the first entry of the next SRH-6LoRH is popped from the next
      SRH-6LoRH and coalesced with the first entry of this SRH-6LoRH.

To get here, the next SRH-6LoRH must be of a higher level of compression,
so it encodes addresses with fewer bytes.  What is the logic to making the
next next 6LoRH smaller (popping), and keeping the larger current 6LoRH?
Why not just drop the current 6loRH here and have fewer bytes, period?

Or am I mis-reading this.  Maybe I have to write an example of what I think
this is saying.

Michael Richardson <mcr+IETF@sandelman.ca>;, Sandelman Software Works
 -= IPv6 IoT consulting =-