Re: [sipcore] Mirja Kühlewind's Yes on draft-ietf-sipcore-dns-dual-stack-07: (with COMMENT)

[[e-mail] (Dale R. Worley)]

"Mirja Kuehlewind (IETF)" <[e-mail]> writes:
> Okay. I think I was confused by the ‚i.e.‘ together with the second
> sentence here:
>
>       The dual-stack client SHOULD look up all address records (i.e.,
>       for all address family(ies) that it supports) for the domain name
>       and add the resulting addresses to the list of IP addresses to be
>       contacted.  A client MUST be prepared for the existence of DNS
>       resource records containing addresses in families that it does not
>       support; if such records may be returned by the client's DNS
>       queries, such records MUST be ignored as unusable and the
>       supported addresses used as specified herein.
>
> Reading it again with your clarification I not sure why I
> misunderstood in the first place. So probably no clarification needed;
> or maybe just remove the ‚i.e.‘ and the brackets..?

Reading it again, the text can be simplified by replacing "all address
records (i.e., for all address family(ies) that it supports)" with
"address records for all address families that it supports".  So I've
made that change.

> One more question: getting an record returned for an address family
> that was not requested is an error case, right? Or can this actual
> happen in ‚normal‘ operation?

It depends on what DNS requests are used.  E.g., if the client does an
ANY request, then it will get both A and AAAA records for the domain
name.  But if there is a new address family, it might receive other
records, and the client must be prepared to ignore them.

>>> And related to this question: Shouldn't it be named "multi-stack client"
>>> instead of "dual-stack client"?
>
> I noticed that the whole doc is written in a way that would correctly
> operate with new address families. That's we I suggested this
> change. I think that this term would be as easily understandable as
> the current dual-stack term. But I don’t have a strong opinion, so
> please just use what you think is better.

I'll ask my coauthors what they think.  They've been working on this
text longer than I have and know its background better.

I've updated the draft -08.  You can see the differences in
https://www.ietf.org/rfcdiff?url1=draft-ietf-sipcore-dns-dual-stack-07&url2=http://svn.resiprocate.org/rep/ietf-drafts/worley/draft-ietf-sipcore-dns-dual-stack-08.txt
and the entire current draft in
http://svn.resiprocate.org/rep/ietf-drafts/worley/draft-ietf-sipcore-dns-dual-stack-08.{txt,html}

Dale