[Int-area] Christopher Inacio's No Objection on draft-ietf-intarea-multicast-application-port-08: (with COMMENT)

[Christopher Inacio via Datatracker <[e-mail]>]

Christopher Inacio has entered the following ballot position for
draft-ietf-intarea-multicast-application-port-08: No Objection

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COMMENT:
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Thanks for the relatively short and concise draft.

First, I support the discusses of my fellow ADs making particularly good points
about socket options, portability, etc.

I would like to focus on the following point though: the authors discuss about
traversing firewalls and that is mostly focused on host-based firewalls.  There
is mention of network firewalls.  What isn't mentioned at all is NAT devices
and any other type of middlebox doing address translation.  Since the NAT might
be changing some of the addresses, even if it isn't discussed in the general
text, in context of network based firewalls it is strangely missing in my
opinion.  This may complicate things - should a NAT+firewall multicast the
packet to its link local network?  What are the right addresses in that case?
What about collisions on that case since there are potentially multiple
destination hosts in a NATed network segment.