Early Review of draft-ietf-softwire-dslite-multicast-12
review-ietf-softwire-dslite-multicast-12-intdir-early-cao-2016-12-14-00

Hi, authors and editors,

I am an assigned INT directorate reviewer for this draft. These
comments were written primarily for the benefit of the Internet Area
Directors. Document editors and shepherds should treat these comments
just like they would treat comments from any other IETF contributors
and resolve them along with any other Last Call comments that have
been received. For more details of the INT directorate, see
<http://www.ietf.org/iesg/directorate.html>.


I do not see any major reason to block the publication of this draft.
Below are two comments for discussion.

a) uPrefix64 and mPrefix64

I was a bit confused when I encounter the name suffix -64, because
they somehow imply only 64-bit long prefix could be used, while the
fact may be not true.  If '64' means an IPv6-IPv4 mapping, it may make
some sense.  So I highly encourage the editors to put some notes below
the items in the terminology section.


b)
6.2.  Multicast Data Forwarding

  When the mB4 receives an IPv6 multicast packet, it MUST check the
   group address and the source address.  If the IPv6 multicast group
   prefix is mPrefix64 and the IPv6 source prefix is uPrefix64, the mB4
   MUST decapsulate the IPv6 header and forward the IPv4 multicast
   packet through each relevant interface.  Otherwise, the mB4 MUST
   silently drop the packet.

comments: the mB4 not only needs to check the validity of mPrefix and
uPrefix, but also needs to check if there exists an associated
MLD/IGMP requests from that prefixes.  Only if there was an IGMP
report associted with this transaction, it will forward such multicast
packets.


Thanks for draft the document.

-zhen