Re: [DNSOP] The Larger Discussion on Differences in Response Drafts

[Bob Harold <[e-mail]>]

On Tue, Aug 16, 2016 at 8:57 AM, Tim Wicinski <[e-mail]> wrote:

> All,
>
>
> In Berlin we had two presentations on different methods of returning
> multiple responses:
>
> https://datatracker.ietf.org/doc/draft-wkumari-dnsop-multiple-responses/
>
> https://datatracker.ietf.org/doc/draft-bellis-dnsext-multi-qtypes/
>
> and a presentation in Buenos Aires:
>
> https://datatracker.ietf.org/doc/draft-vavrusa-dnsop-aaaa-for-free/
>
> All of these documents are attempting to solve a larger problem in
> different ways.
> The end result is "Return Associated Answer" to the client.
>
> The question is starting to coalesce around these two premises:
>
> - Do we want to Server to PUSH any or all Associated Answers, or
>
> - Do we want the Client to PULL any or all Associated Answers, or
>
>
> There are times when the client knows that it will need multiple pieces of
information, and an efficient way to ask several questions at once is
valuable.
The client would have to track whether the server has trouble with the
requests and fall back to single requests.

There are times when the server knows that the client is likely to want
certain records once it gets an answer, and if it can include those, there
is a benefit.
Those can be records based on the answer - for example an SRV lookup is
likely to want an A and AAAA next.
Or they can be outside knowledge that the server is given or learns - like
if a particular web page is looked up, then these others hosts are likely
to be looked up next for other parts of that web page.
I think that the client should have a way to signal support for this, and
the server only add records if the client signals support.

I say "client" but I think the same could be useful at each link in the DNS
lookup.

-- 
Bob Harold