Subject: RE: [mobile-ip] BU Authorization method: bidding down

From: [email-masked]
Date: Tue, 12 Feb 2002 09:30:22 -0600

Erik Nordmark [[email-masked]] wrote:
>
>
>Question is whether this matters in the large scheme of things for
>MIPv6.

The current scope of the security problem for MIPv6 binding updates is
solved by the RR approach. Hence the need for solutions that offer a
greater degree of security for BUs should be independently pursued.

>Such an attacker can just drop data packets as a DoS attack and can
>already (by virtue of being on the path and thereby being able to prevent RO)
>see all the data packets (and modify them unless they are protected by
>higher layer security like IPsec or TLS).
>So does CGA, as we understand it today, really make a significant enough 
>difference for MIPv6?

CGA needs to be explored more before it is used by MIPv6 or for doing
other things that you mention below. In order to get the base MIPv6
specification out, discussion of the CGA solution in the base spec
should be extremely limited. An active attacker on the HA-CN path can
do harm to communication irrespective of RR or CGA. The MITM (HA-CN)
problem is not something that MIPv6 needs to solve. 

>(I continue to believe that CGA would be a useful tool in authrizing e.g.
>MLD joins for anycast groups, preventing DAD and address resolution spoofing
>on a link, but those approaches might not need a bit in the address - to
>early to tell.)
>
>   Erik
>

-Basavaraj