Subject: [DNSOP] Stephen Farrell's Yes on draft-ietf-dnsop-dns-terminology-04: (with COMMENT)

From: "Stephen Farrell" <[email-masked]>
Date: Tue, 15 Sep 2015 09:46:09 -0700

Stephen Farrell has entered the following ballot position for
draft-ietf-dnsop-dns-terminology-04: Yes

When responding, please keep the subject line intact and reply to all
email addresses included in the To and CC lines. (Feel free to cut this
introductory paragraph, however.)

Please refer to https://www.ietf.org/iesg/statement/discuss-criteria.html
for more information about IESG DISCUSS and COMMENT positions.

The document, along with other ballot positions, can be found here:
https://datatracker.ietf.org/doc/draft-ietf-dnsop-dns-terminology/

----------------------------------------------------------------------
COMMENT:
----------------------------------------------------------------------

Thanks for this. 

Is a domain a sub-domain of itself? Do we care? The definition
of Alias might imply that we do. Not sure.

---

From: "Paul Hoffman" <[email-masked]>
Date: Fri, 18 Sep 2015 11:55:13 -0700

On 15 Sep 2015, at 9:46, Stephen Farrell wrote:

> Is a domain a sub-domain of itself?

No. The quoted definition from RFC 1034 starts off "A domain is a 
subdomain of another domain..." There is no language in RFCs 1034 or 
1035 that indicate that a domain can be a subdomain of itself.

> Do we care?

We would if it could be, since there could be ramifications.

--Paul Hoffman

---

From: Stephen Farrell <[email-masked]>
Date: Fri, 18 Sep 2015 21:14:53 +0100

Hiya,

> 1035 that indicate that a domain can be a subdomain of itself.

In 1034, 3.1? I don't think that answers this question tbh. That
says:

"A domain is a subdomain of another domain if it is contained
within that domain."

That'd answer the question if it said iff but it says if.

> We would if it could be, since there could be ramifications.

IIRC your document doesn't say either.

Now I guess that might be the correct stance, but maybe it's one
to [onder on the dnsop list at some other appropriate time. OTOH,
since the DNS has survived and prospered regardless, it may be
fine to just not bother.

S.

---

From: manning <[email-masked]>
Date: Fri, 18 Sep 2015 13:14:44 -0700

On 18September2015Friday, at 11:55, Paul Hoffman <[email-masked]> wrote:

> No. The quoted definition from RFC 1034 starts off "A domain is a subdomain of another domain..." There is no language in RFCs 1034 or 1035 that indicate that a domain can be a subdomain of itself.

	I’m going to sit with Stephen on this specific idea.   Set theory supports the claim that a domain can be a sub-domain of itself.  Indeed RFC 973 calls out the original specifications (RFC 882, RFC 883) 
allowed for recursion and inheritability and suggests that these constructs had value and merit, but IMPLEMENTATION problems suggested not allowing them.     So if one were to capture this implementation artifact in a terminology document, it would be a good to point out why this implantation artifact exists.

> _______________________________________________
> DNSOP mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/dnsop

---

From: "Paul Hoffman" <[email-masked]>
Date: Fri, 18 Sep 2015 14:09:34 -0700

> That'd answer the question if it said iff but it says if.

I'm not sure what you're asking for here. RFC 1034 is the definition of 
"subdomain" that we have today (well, for the past few decades). Are you 
just pointing out that it did not consider the case of a domain being a 
subdomain of itself? Or are you wanting us to update RFC 1034 and pick a 
yes/no on the issue? Or...?

> IIRC your document doesn't say either.

Correct.

> since the DNS has survived and prospered regardless, it may be

That seems to be a reasonable course of action for now.

--Paul Hoffman