Re: [v6ops] I-D Action: draft-colitti-v6ops-host-addr-availability-01.txt

[Gert Doering <[e-mail]>]

Hi,

On Tue, Jul 28, 2015 at 03:58:04PM +0200, Andrew ????  Yourtchenko wrote:
> I did not look at it as a problem given that every mobile phone on
> IPv6 will already get a /64 per host, and the number of mobile phones
> is dramatically bigger than the number of fixed installations.

Bigger than then number of L2 *segments*, undoubtly.

But no way bigger than "the number of devices that could attach to
a L2 link" - as all these mobile phone also has wifi, so you have way
more devices that attach to "shared links".

Network structure is also way different - in mobile, all devices attach
to some sort of aggregation router (via 3G PDP tunnels etc) - while
in "classic" networking, you have a multitude of independent segments
that do not normally have aggregation infrastructure or provisioning
available.  Prefix mobility in a typical enterprise networks (where
you'd have enough devices in a L2 segment to start think about scaling)
isn't really there.

> But I pulled that assumption more or less out of my thumb, based on
> observed anecdata, so would be happy to be proven wrong.
> 
> If we say we want to absolutely avoid NAT, then something has to give,
> and I don't know which tradeoff is a better one, both can be argued
> for and against. I think we might need both.

If you want my opinion, I think DHCPv6-PD to single hosts (= not something
that does tethering) is not a reasonable approach.

If something does tethering, you need to decide what you're talking about,
"enterprise-ish", "mobile" or "homenet".  In mobile, DHCPv6-PD, or just
sharing the PDP /64.  In homenet, HNCP or DHCPv6-PD.  In the enterprise?  
No idea what can be implemented with the typical constraints on 
trackability, security, etc.  (like: if the device attaches to *this* 
network, it's permitted to go *there* by IP ACLs - whether or not this 
is a reasonable approach in itself anymore stands to be debated, but it 
will be with us for a long time).

Gert Doering
        -- NetMaster
-- 
have you enabled IPv6 on something today...?

SpaceNet AG                        Vorstand: Sebastian v. Bomhard
Joseph-Dollinger-Bogen 14          Aufsichtsratsvors.: A. Grundner-Culemann
D-80807 Muenchen                   HRB: 136055 (AG Muenchen)
Tel: [phone]           USt-IdNr.: DE813185279