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[mpls] I-D ACTION:draft-ietf-mpls-multicast-encaps-01.txt

  • From: Eric Rosen <erosen@cisco.com>
  • Date: Wed, 20 Sep 2006 15:10:59 -0400
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> The draft essentially redfines ethertype 0x8848 to mean "the top label
> is an upstream assigned MPLS multicast label", so why in section 5, GRE
> if all the encapsulated MPLS packets have an upstream assigned label is
> the Ethertype set to 0x8847?

A very good question.   I think what I originally had in  mind was that 8847
is used  when all the labels  are of the  same type, and the  combination of
8847 and  8848 is used when there  are labels of both  types.  However, that
really doesn't seem to make any sense.

After some discussion  among the co-authors, we are  inclined to change this
so that 8847  is used for downstream-assigned labels  and 8848 for upstream-
assigned labels, irrespective of whether it is known apriori that the tunnel
carries only one of the two categories of label.

If it is known apriori that all  the packets on a GRE tunnel carry upstream-
assigned labels,  then a  packet with  the 8847 codepoint  would then  be an
error, and should be discarded.

The text of the draft will be adjusted. 

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