Re: 64bit MAC addresses and SLAAC

On Wed, Jun 17, 2020 at 3:08 PM Fernando Gont <fgont@si6networks.com> wrote:

> On 17/6/20 13:42, Philip Homburg wrote:
> >> The case of "same IID with distinct prefixes" is the same as using
> >> the same IID as the host moves from one network to another. And
> >> that's quite bad for privacy. PLease see RFC7721.
> >
> > I think they are quite different. If a host moves between different
> networks
> > and keeps the same IID, then the movements of the host can be tracked.
> >
> > If a host is connected to a subnet that has multiple prefixes, then using
> > the same IID for all prefixes only has marginally less privacy than
> > using different IIDs.
>
> Well, it does allow correlation of network activities across addresses.
> In a way, that's kind of the same as when a host moves across networks.
>
>
>
> > That said, in my opinion people who want any kind of control over what
> > addresses are used, should use DHCPv6 (Or manual/static configuration)
>
> +1
>

   Of course the caveat there with unmanaged network and SOHO and Mobile
where manual or DHCPV6 is not possible or viable.  In those cases SLAAC is
preferred, but then we have the crux of issue and the decision tree on
privacy random IID and it’s overhead if it’s not necessary versus modified
EUI64.  Based on decision tree of course the underlying operational impacts
of random versus  stable IID double edged sword operator or individuals
decision to pick which works best for their use case.  In the end net-net
is what is simplest to deploy and least overhead but also meets the desired
goal is generally the thought for picking the IID generation solution. For
that SLAAC wins out in that decision for the use case described above.

>
>
> --
> Fernando Gont
> SI6 Networks
> e-mail: fgont@si6networks.com
> PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492
>
>
>
>
> --------------------------------------------------------------------
> IETF IPv6 working group mailing list
> ipv6@ietf.org
> Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
> --------------------------------------------------------------------
>
-- 

<http://www.verizon.com/>

*Gyan Mishra*

*Network Solutions A**rchitect *

*M 301 502-134713101 Columbia Pike *Silver Spring, MD