Re: 64bit MAC addresses and SLAAC

[Philip Homburg <[e-mail]>]

>   Of course the caveat there with unmanaged network and SOHO and Mobile
>where manual or DHCPV6 is not possible or viable.  

Why is DHCPv6 not possible? Of course there is the Android problem.
But I doubt that a low power IoT device would share a wifi-link with an
Android device.

>    In those cases SLAAC is preferred, but then we have the crux of
>    issue and the decision tree on privacy random IID and its overhead
>    if its not necessary versus modified EUI64.  
>    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.

A stable, unique pseudo random IID per prefix basically requires one
SHA2-HMAC (or equivalent in SHA3 or other modern hash function) per 
prefix.

I cannot imagine that computing 2 SHA2 hashes has a significant amount
of energy use compared to link attachment and duplicate address detection.

This computation is once per prefix, so it becomes an issue if the
devices frequently attaches to new links. In which case tracking protection
becomes important.

I also wonder, a device that cannot afford a couple SHa2 hashes? Then that
device is probably insecure and should not be connect to the internet
anyhow.