Default security functions on an IPv6 CPE

[Fernando Gont]

On 05/30/2011 09:58 PM, Doug Barton wrote:
> On 05/30/2011 17:07, Fernando Gont wrote:
>> IIRC, one of the arguments was that, if e.g. there's a single host
>> active in a given subnet, even if it varies its address, it's easy to
>> figure out that its simply the same host varying its Interface ID
>> (particularly when the address itself is claiming that it si a temporary
>> address;-)  ).
> 
> That's not the problem that privacy addresses were intended to solve.
> The real issue is that if you take the same host (laptop, whatever) and
> use it on different networks you can still be tracked because the host
> part of the address is (intended to be) globally unique. Regarding that
> threat model, privacy addresses are effective.

I'd have to re-read RFC4941. But my take is that if it has a requirement
for short-lifetime addresses, that seems to be targeting the issue I
discussed -- if not, the address could simply be randomized and used for
a long time.

Thanks,
-- 
Fernando Gont
e-mail: fernando at gont.com.ar || fgont at acm.org
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1