Re: [DNSOP] Eric Rescorla's No Objection on draft-ietf-dnsop-attrleaf-13: (with COMMENT)

Dave Crocker <dhc@dcrocker.net> Wed, 10 October 2018 20:18 UTC

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From: Dave Crocker <dhc@dcrocker.net>
To: Eric Rescorla <ekr@rtfm.com>, The IESG <iesg@ietf.org>
Cc: draft-ietf-dnsop-attrleaf@ietf.org, dnsop-chairs@ietf.org, Benno Overeinder <benno@NLnetLabs.nl>, dnsop@ietf.org, Tim Wicinski <tjw.ietf@gmail.com>
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Date: Wed, 10 Oct 2018 16:18:47 -0400
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Subject: Re: [DNSOP] Eric Rescorla's No Objection on draft-ietf-dnsop-attrleaf-13: (with COMMENT)
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Eric,

On 10/9/2018 7:23 PM, Eric Rescorla wrote:
>>       However some services have defined an operational convention, which
>>       applies to DNS leaf nodes that are under a DNS branch having one or
>>       more reserved node names, each beginning with an _underscore.  The
>>       underscored naming construct defines a semantic scope for DNS record
>>       types that are associated with the parent domain, above the
>>       underscored branch.  This specification explores the nature of this
> 
> This text is a bit hard to parse for the layman. Here's my attempted
> rewrite, which captures what I think this means.
> 
> Conventionally, this construct associates data with the parent domain,
> with the underscored label instead denoting the type of the data.
> 
> I'm not sure if that helps, but perhaps something along these lines?

Yeah, this has been an oddly challenging bit of text to formulate.  Perhaps:

      However some services use an operational convention for defining 
specific interpretations of an RRset, by locating the records in a DNS 
branch, under the parent domain to which the RRset actually applies. 
The top of this subordinate branch is defined by a naming convention 
that uses a reserved node name, which begins with an _underscore.


> S 1.1.
>>    
>>    1.1.  Underscore Scoping
>>    
>>       As an alternative to defining a new RR type, some DNS service
>>       enhancements call for using an existing resource record type, but
>>       specify a restricted scope for its occurrence.  Scope is meant as a
> 
> I think I get why you are saying "scope" here, but it's kind of not
> that good fit with the programming concepts of scope as I am familiar
> with.

    So I took your concern as an excuse to review the CS definition and 
find that I still think its application here is appropriate...  And it 
has not seemed to cause confusion for others.


> S 2.
>>                          +----------------------------+
>>    
>>                           Examples of Underscored Names
>>    
>>       Only global underscored names are registered in the IANA Underscore
>>       Global table.
> 
> so just for clarify, in the examples above, only _service[1-4] and
> _authority would need to be registered?

Yes.  (And I've added a sentence noting that point, for clarity. Thanks.)

d/


-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net