Re: [Doh] operational considerations

Eliot Lear <lear@cisco.com> Mon, 20 November 2017 06:06 UTC

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To: Patrick McManus <pmcmanus@mozilla.com>
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From: Eliot Lear <lear@cisco.com>
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Date: Mon, 20 Nov 2017 07:05:57 +0100
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Subject: Re: [Doh] operational considerations
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Hi Patrick,

This is good text.  I think Jim has a point about "default resolver". 
Also, further reduction is possible.  See below:


On 11/19/17 2:48 AM, Patrick McManus wrote:
> Hi Eliot - indeed this is fairly brief.. thank you. if we can keep it
> to this scope I'm ok - but if the section begins to grow organically
> we should really discuss moving to a different doc. I have a proposed 
> minor rework of your text below which I believe to be more concise and
> a bit more illuminating on the root issues. Let me know what you think.
>
> Operational Considerations
>
> Different DNS servers may provide different results to the same query.
> It logically follows that which server is consulted influences the end
> result. Split-horizon DNS [RFC6950] is a specific example of this
> approach where the answers are derived from the (potentially natted)
> source of the query. A client that chooses to query a non-default
> resolver for a name that is using this style of algorithm may not
> obtain correct results.

s/chooses to query/queries/

s/non-default resolver/resolver that is not proximate/

How's that?
>
> The HTTPS channel used by this specification establishes secure two
> party communication between the DNS API Client and the DNS API Server.
> Filtering or inspection systems that rely on unsecured transport of
> DNS will not function in a DNS over HTTPS environment.

Eliot