Re: [DNSOP] I-D Action: draft-ietf-dnsop-edns-client-subnet-07.txt

[Mukund Sivaraman <[e-mail]>]

On Mon, Mar 21, 2016 at 06:22:52PM -0700, 神明達哉 wrote:
> At Tue, 22 Mar 2016 01:15:48 +0530,
> Mukund Sivaraman <[e-mail]> wrote:
> 
> > > > (1) Section 7.2.1.  Authoritative Nameserver:
> 
> > > I'm confused about the revised Section 7.2.1 regarding overlapping
> > > prefixes.  The 07 version of the draft now states:
> > >
> > >    [...]  Because it can't be guaranteed that queries for all
> > >    longer prefix lengths would arrive before one that would be answered
> > >    by the shorter prefix length, an Authoritative Nameserver MUST NOT
> > >    overlap prefixes.
> > >
> > > But the above "trivial example" seems to talk about what an
> > > authoritative nameserver would do if it overlaps prefix...doesn't it
> > > simply break the MUST NOT in the first place?
> >
> > When overlapped address prefixes occur in zone data (the configuration
> > provided by an administrator to the authoritative nameserver), the
> > authoritative server should resolve the overlap by deaggregating
> > prefixes such that the prefixes in the Authoritative Nameserver's reply
> > messages do not overlap.
> 
> At least to me, "MUST NOT overlap" can't obviously read that way.  I
> think some more wording clarification is needed.  Also, what about
> the "warn and continue" behavior of this one?
> 
>    2.  Alert the operator that the order of queries will determine which
>        answers get cached, and either warn and continue or treat this as
>        an error and refuse to load the configuration.
> 
> If it's not considered a violation of the MUST NOT, I think we need
> more explanation here, too.

You're right. It should be described more clearly.

		Mukund