Re: draft-gont-6man-managing-privacy-extensions-00.txt

[Fernando Gont <[e-mail]>]

Hi, Brian,

On 15/03/2011 07:16 p.m., Brian E Carpenter wrote:
>>> I agree. I sort of accept that an ISP can know my addresses in use, in
>>> part because they gave them to me. However, for an ISP to not let me
>>> choose if I want to use privacy addresses on the Internet would
>>> be completely unacceptable.
>>
>> Why would you find it acceptable to have the ISP assign you the complete
>> address e.g. with DHCP, then?
> 
> In the context of a user requiring privacy protection, it isn't acceptable.

Then what's all this controversy with
draft-gont-6man-managing-privacy-extensions? :-) -- That aside, there
have been quite a few publications asessing the real "privacy" provided
with the so-called privacy-extensions....


> As far as I know, what the ISP will assign is a prefix; the individual
> host addresses are locally assigned by the CPE.

Yep, sorry. I meant "CPE", not "ISP".


> Thus, in an Internet cafe, a user using privacy addresses can be traced
> to the cafe but no further, even if the cafe is also using DHCP to
> assign addresses.

If your threat model is that the CPE is maliciously recommending hosts
not to use privacy addresses, the CPE might as well claim that DHCP is
needed, and assign to each host an IPv6 address that is based on the
EUI-64 of that host...

P.S.: Bottom-line is: This is about improving the manageability of the
address generation policy. Thus, even if different systems have
different defaults, a router can provide advice such that they all
employ the same address generation policy (whether EUI-64, privacy
addresses, or whatever).

Thanks,
-- 
Fernando Gont
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