Re: [rtcweb] Transports: RFC 4941 support?

[Ted Hardie <[e-mail]>]

On Thu, Mar 20, 2014 at 10:07 AM, Dan Wing <[e-mail]> wrote:

>
> On Mar 20, 2014, at 9:34 AM, Justin Uberti <[e-mail]> wrote:
>
>
>
>
>
> So perhaps:
>>    "An RTCWEB implementation SHOULD prefer to use temporary addresses
>> [RFC4941] where host and network policy permit [RFC6724]."
>> ?
>>
>
> I think it needs to be stronger than that - something like
> "where
> 
> host and network policy permit, RTCWEB implementations SHOULD gather IPv6
> temporary addresses and SHOULD NOT gather non-temporary addresses".
>
> Preferring to use temporary addresses is probably not sufficient to
> prevent linkage, since you will have connectivity checks from the
> non-temporary addresses. (i.e. an eavesdropper listening over an extended
> period of time could determine calls are from the same endpoint)
>
>
> Agreed.  I like your suggested wording.
>
> -d
>
>
>
So, I note that in this case where a non-temporary IPv6 address is present
and  no temporary IPv6 address is present, this appears to push IPv6 out of
the gathered list completely.  If I have that right, then my view as an
individual is that this is the wrong result.  It will either force the use
of IPv4 addresses which are just as linkable as IPv6 non-temporary
addresses or rely on NATs to get the non-linkability (and provide us all
the other subtle joys of NAT).

As a friendly amendment, may I suggest "Where both non-temporary and
temporary addresses are present and host and network policy permit, RTCWEB
implementations SHOULD gather IPv6 temporary addresses and SHOULD NOT
gather non-temporary addresses"?

I also confess to a suspicion that Harald's view is the most
sensible--having a separate policy for this application either won't happen
or doesn't make much sense.  But if we have one, I'd prefer one that
doesn't shove IPv6 out the door completely if the host doesn't use
temporary addresses.

regards,

Ted