Re: Node Requirements: Elevating DHCPv6 from MAY to SHOULD

["Brzozowski, John" <[e-mail]>]

Interesting point Bob raises.

Thomas,

Is the intention for the new text to relax the requirement for
auto-configuration?  The new DHCPv6 text should be in addition to support
for stateless auto-configuration to ensure other deployment models are
supported.

John
=========================================
John Jason Brzozowski
Comcast Cable
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o) 609-377-6594
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w) http://www.comcast6.net
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On 5/13/11 11:55 AM, "Bob Hinden" <[e-mail]> wrote:

>Thomas,
>
>On May 13, 2011, at 6:37 AM, 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?
>> 
>> 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.
>
>While I support changing the requirement to a SHOULD, I would prefer the
>text to be something like:
>
>     	<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.   There will be a wide range of IPv6 deployment models
>        and differences in address assignment requirements.  Consequently
>all hosts
>	SHOULD implement address configuration via DHCP.</t>
>
>It's not just about what some operators may or may not do.  For example
>enterprises, governments, etc. will also have specific requirements.
>
>Bob
>
>
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