Re: RS sending in draft-ietf-v6ops-ipv6-cpe-router-04

[Wojciech Dec <wdec@cisco.com>]

On 29/04/2010 02:38, "Hemant Singh (shemant)" <shemant@cisco.com> wrote:

> -----Original Message-----
> From: owner-v6ops@ops.ietf.org [mailto:owner-v6ops@ops.ietf.org] On
> Behalf Of Wojciech Dec (wdec)
> Sent: Monday, April 26, 2010 10:50 AM
> To: Philip Homburg
> Cc: v6ops@ops.ietf.org
> Subject: Re: RS sending in draft-ietf-v6ops-ipv6-cpe-router-04
> 
> 
>> The issue is one of overwriting ND cache entries in the BNG, by having
> one
>> customer spoof another's LL address.
> 
> Hmm, unless the DSL deployment is explained better in an IETF document
> we will thrash forever discussing issues in DSL.  So now I can only
> reply based on a guess for what the DSL network may look like.  Why is
> the BNG not using some identifier like a line id and not letting another
> customer spoof a LL address in the BNG's neighbor cache?  The  DSL
> broadband standards should be able to fix such a basic problem.

There is NOTHING DSL specific about IPv6 address spoofing on a shared access
medium (eg ethernet, docsis, wireless, etc).
In order to use a line-id, there has to be some way of associating the
line-id to an address. If the line-id arrives in an RS message without an IP
address, doing so gets complicated.

-Woj.

> 
> Hemant