Re: Node Requirements: Elevating DHCPv6 from MAY to SHOULD

[Ralph Droms <[e-mail]>]

Thomas...

On May 13, 2011, at 9:37 AM 5/13/11, Thomas Narten wrote:

> Per a previous thread, there are indications that the WG may now be
> willing to recommend that DHCPv6 be a SHOULD for all hosts. This is
> based on the following rationale:
> 
> Thomas Narten <[e-mail]> writes:
> 
>> I personally would support having DHCP be a SHOULD rather than a
>> MAY. The justification in my mind is that if you want the network
>> operator to have the choice of whether they want to use  Stateless
>> addrconf OR DHCP, they only have that choice of devices widely
>> implement both.
> 
> This was supported by some others, particularly now that it is clear
> there are more implementations of DHCPv6, e.g.:
> 
> Bob Hinden <[e-mail]> writes:
> 
>> While my personal view is that DHCPv6 won't be used for host
>> configuration in cable/DSL deployments (except for provisioning the
>> prefix to the home router), it appears that DHCPv6 is being widely
>> implemented in host OS's because it is needed some environments.
>> There are enough variations in deployment models that a host
>> developer will need to support both.
> 
>> Based on this, I think a SHOULD is OK. 
> 
> Let me propose the following change be made to the node requirements
> document:
> 
> OLD/Current:
> 
>   DHCP can be used to obtain and configure addresses.  In general, a
>   network may provide for the configuration of addresses through Router
>   Advertisements, DHCP or both.  At the present time, the configuration
>   of addresses via stateless autoconfiguration is more widely
>   implemented in hosts than address configuration via DHCP.  However,
>   some environments may require the use of DHCP and may not support the
>   configuration of addresses via RAs.  Implementations should be aware
>   of what operating environment their devices will be deployed.  Hosts
>   MAY implement address configuration via DHCP.
> 
> New:
> 
>      	<t> DHCPv6 <xref target='RFC3315' /> can be used to obtain and
> 	configure addresses. In general, a network may provide for the
> 	configuration of addresses through Router Advertisements,
> 	DHCPv6 or both.  Some operators have indicated that they do
> 	not intend to support stateless address autoconfiguration on
> 	their networks and will require all address assignments be
> 	made through DHCPv6. On such networks, devices that support
> 	only stateless address autoconfiguration will be unable to
> 	automatically configure addresses. Consequently all hosts
> 	SHOULD implement address configuration via DHCP.</t>
> 
> 
> Is this acceptable?

Looks fine and appropriate to me, with one nit: s/DHCP/DHCPv6/ in the last line.

- Ralph

> Please respond yes or no. Given the WG's previous hesitation to having
> DHCPv6 be a SHOULD, it is important that we get a clear indication of
> whether or not the WG supports this change.
> 
> Thomas
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