Re: I-D Action: draft-ietf-6man-rfc6434-bis-01.txt

[David Farmer <[e-mail]>]

On Sun, Jul 16, 2017 at 6:25 AM, Lorenzo Colitti <[e-mail]> wrote:

> On Sun, Jul 16, 2017 at 1:20 PM, Nick Hilliard <[e-mail]> wrote:
>
>> The self-selection addressing model does not suit the deployment
>> requirements for many types of ipv6 networks, including enterprise,
>> provider hosting, terrestrial access networks (e.g. docsis / gpon /
>> ipoe) and others.  If the recommendation for dhcpv6 is dropped, then
>> there is no recommended ietf model for operator-assigned addressing, and
>> this would leave a glaring hole in the ipv6 host specification.
>>
>
> That's a fair opinion to hold, but the fact of the matter is that a SHOULD
> for DHCPv6 conflicts with RFC 7934 and RFC 7844.
>
> We shouldn't publish a host requirements document that contradicts the
> host address assignment BCP and that cites RFC7844 while contradicting that
> document's recommendation to use stateless in preference to stateful.
>

Lets start with RFC 7934 it is a set of RECOMMENDATIONS for how networks
should supply addresses to general purpose hosts.  First, not everything
fits into that scope and even within that scope as a RECOMMENDATION that
means "there may exist valid reasons in particular circumstances to ignore
a particular item" [RFC2119].  So, it by no means precludes the possibility
that hosts could find them on a network that is only providing addresses
via DHCPv6. Therefore, a SHOULD for DHCPv6 in the host requirements still
seems appropriate to me.

As for RFC 7844, it is scoped to mobile hosts that want privacy from the
DHCP server, and it says "The anonymity profiles have the effect of hiding
the client identity from the DHCP server.  This is not always desirable.
..."  A document that itself recognizes it's primary purpose "is not always
desirable" even within it's defined scope, isn't a strong argument for
changing the RECOMMENDED behavior of all host.

Further, a "recommendation to use stateless in preference to stateful"
isn't a prohibition on stateful, Until, stateful is prohibited or all
networks are required to provided stateless, a SHOULD for DHCPv6 in the
host requirements still seems appropriate to me.

Thanks.

-- 
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