Re: Proposed change to draft-ietf-6man-multi-homed-host after IESG review

[Tim Chown <[e-mail]>]

Hi,

> On 16 Sep 2016, at 01:49, Fernando Gont <[e-mail]> wrote:
> 
> On 09/15/2016 05:53 PM, Brian E Carpenter wrote:
>> Hi,
>> 
>> This message concerns
>> https://tools.ietf.org/html/draft-ietf-6man-multi-homed-host-09 .
>> 
>> There is one remaining issue in the draft before it can get IESG approval.
>> One of the routing ADs proposes the following change. It does not affect
>> the normative content of the draft, but it is a technical change (deletion)
>> so we'd like to hear if there are any objections from the WG. Please comment
>> within a week (silence means no objection to this change). Some more
>> background is below the proposed change.
>> 
>> OLD:
>> 
>> 2.2.  Expectations of multihomed networks
>> 
>>   The mechanism specified in this document requires some form of
>>   support from the routing protocols used in multihomed networks.  One
>>   such way of providing the requisite support in routing protocols is
>>   described in a routing protocol independent fashion
>>   [I-D.ietf-rtgwg-dst-src-routing].  Network designs exist that can
>>   usefully limit themselves to static routing (such as a simple tree
>>   network), or may internally use no routers at all, such as a single
>>   LAN with two CE routers, each of which leads to a different upstream
>>   network.
>> 
>> NEW:
>> 
>> 2.2.  Expectations of multihomed networks
>> 
>>   Network designs exist that can usefully limit themselves to static
>>   routing (such as a simple tree network) or may internally use no
>>   routers at all, such as a single LAN with two CE routers, each of
>>   which leads to a different upstream network.  However, the
>>   mechanism specified in this document may require some form of
>>   support from the routing protocols used in some multihomed networks.
>>   The details of such support are out of scope for this document.
>> 
>> You can see Alia's original DISCUSS comment dated 2016-08-02 at
>> https://datatracker.ietf.org/doc/draft-ietf-6man-multi-homed-host/history/ .
>> The "SHOULD" mentioned there has already been removed, but her considered
>> opinion is that the routing solution is simply out of scope for this draft.
> 
> Isn't the reference to [I-D.ietf-rtgwg-dst-src-routing] simply
> informational?
> 
> If my mental diff (not having slept for quite too many hours) doesn't
> fail, the only different between OLD and NEW is s/requires&may require/
> and the deletion of the (alas informative) reference.
> 
> The s/requires/may require" seems to be incorrect (unless I'm missing
> something). The informational diff shouldn't be a show-stopper (whether
> included or removed... although I'd keep it, given the option).

The question is whether a specific draft informational document needs to be cited explicitly as an example. I recall when we finalised RFC7368 for the Homenet architecture, we were guided to remove similar such references there, but to retain their spirit in the text.

I note that draft-ietf-6man-multi-homed-host doesn’t cite RFC7368, which mentions the utility of src/dst routing in sections 3.1.2, 3.2.4 (twice) and 3.5.1, with referring to any specific related draft at the time of that RFC being published. I think what was said then, at least two years ago, still holds.
 
Tim