Re: [DNSOP] DNS Terminology: Glue

[Shumon Huque <[e-mail]>]

On Thu, Mar 12, 2015 at 11:27 AM, Paul Hoffman <[e-mail]>
wrote:

> On Mar 12, 2015, at 5:07 AM, Niall O'Reilly <[e-mail]> wrote:
> >  In http://www.ietf.org/id/draft-hoffman-dns-terminology-02.txt,
> >  "glue" is defined as follows.
> >
> >   Glue records -- Resource records which are not part of the
> >   authoritative data, and are address resource records for the servers
> >   listed in the message.  They contain data that allows access to name
> >   servers for subzones.  (Definition from RFC 1034, section 4.2.1)
> >
> >  Reference to "the message" seems to be a distraction here.  The
> >  cited source defines (and motivates) glue records, in a section
> >  which specifies "[t]he data that describes a zone", as follows
> >
> >   [...] a zone contains "glue" RRs which are not
> >   part of the authoritative data, and are address RRs for the servers.
> >   These RRs are only necessary if the name server's name is "below" the
> >   cut, and are only used as part of a referral response.
> >
> >  I think that placing the definition of glue in the scope of "the
> >  message" rather than in that of the zone data is likely to lead to
> >  confusion.
>
> Quite right. We'll fix this in the next draft.
>

It might be worth also clarifying another thing. The definition states
"These
RRs are only necessary if", but doesn't clearly include or exclude the
possibility
that other address records for NS names that don't sit below the zone cut,
and
were gratuitously provided in the referral response, qualify to be  called
'glue'. I
think  they should not be called glue (they don't meet my intuitive
understanding
of the meaning of 'glue', as gluing up a hole in the resolution path). But
clarity on
this point would be welcome.

Shumon Huque