Subject: Comments on RT-Constrain issues for draft-zzhang-l3vpn-mvpn-global-table-mcast

From: Jeffrey Haas <[email-masked]>
Date: Mon, 9 Jun 2014 10:23:40 -0400

L3VPN,

As part of resolving some interoperability issues between Juniper and
another vendor for the MDT SAFI while using the Constrained Route Target
distribution mechanism (rt-constrain, RFC 4684), it was noted that the
behavior of rt-constrain while being used on "VPN" routes with no Route
Targets was not specified.  

The behavior thus observed was that when rt-constrain was present, routes
lacking RTs may not be distributed.  This behavior would impact the Global
Table Multicast feature.

I started a thread on IDR to discuss this issue:

http://www.ietf.org/mail-archive/web/idr/current/msg13162.html

The thread somewhat abruptly ends since the participants decided to iterate
a bit less publicly.  A clarification Internet-Draft will likey result prior
to the upcoming IETF session in Toronto.  However, in the mean-time, please
be aware of this issue and its presence in various vendors and thus its
impact on this proposal.

-- Jeff