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Colleagues, I may be missing something, but it appears
that, in the cases described, the two hosts downstream of two separate cable
modems are off link to each other. This brings up the question: Do there two
cable modems constitute two virtual interfaces, like two VLANs on the same
physical router interface? If so, this is an architectural, rather than an implementation,
question. Thoughts? Best Regards, (301) 448-6965 (mobile) From:
ipv6-bounces@ietf.org [mailto:ipv6-bounces@ietf.org] On Behalf Of Hemant Singh (shemant) Yes,
in a cable deployment even if two cable modems (CM) in two different homes on
the same upstream physical layer to the Cable edge router (CMTS) cannot talk
directly to each other â they have to send their data to the CMTS who then
forwards the data to the other modem. Still I am not convinced of
any implications for DAD in SLAAC? Without any loss of generality, I will
only refer to a CMTS for the rest of the discussion but the same is applicable
to a DSLAM (or whatever L3 router sits upstream of the DLAM as the first-hop
IPv6 router). Since the CMTS sees all DAD messages from client in the
downstream, if the CMTS detects a dup, the CMTS sends a NA to the client
- problem solved. Of course, now the CMTS is doing ND Proxy which
is already specified in cable standards and implemented on Docsis 3.0 IPv6 CMTS
routers. What did I miss? If
the BBF has any new multicast architecture for ND that I have not accounted
for, please send me your arch doc and I can look at it and reply to that as
well. Hemant From:
owner-v6ops@ops.ietf.org [mailto:owner-v6ops@ops.ietf.org] On Behalf Of Fred Baker (fred) Gentlemen: I'm writing to you as the authors of RFCs 4861 and 4862. In a past
meeting, I think the one in March, an issue came up in Savi that has now been
brought to our attention in a formal manner. The problem is that in certain
access network technologies, notably DSL and I believe Cable Modem, the
connectivity between the CPE host or router and the ISP's first hop router is
siloed - it looks like an Ethernet to the host but in fact is separated into
separate channels. The effect is that while the ISP router can speak to and
hear all of the CPEs it is connected to, the CPEs cannot hear each other. This
has implications for Duplicate Address Detection in SLAAC. We look forward to your advice. Fred Baker IPv6 Operations Begin forwarded message: From: Robin Mersh <rmersh@broadband-forum.org> Date: November 6, 2009
1:42:05 AM GMT+08:00 To: fenner@fenron.com, christian.vogt@ericsson.com, fred.baker@cisco.com, kurtis@kurtis.pp.se, dromasca@avaya.com, rbonica@juniper.net, rdroms@cisco.com, jari.arkko@piuha.net, Mark Townsley <townsley@cisco.com> Subject: Broadband
Forum liaison to IETF on IPv6 security Dear colleagues, For your review, please see the liaison from the Broadband Forum
attached below. Best regards, Robin
Mersh COO The
Broadband Forum phone:
+1 336 288 8013 cell:
+1 303 596 7448 email: rmersh@broadband-forum.org |