Subject: Re: How long can an NS chain be?

From: Dean Anderson <[email-masked]>
Date: Wed, 06 Jan 1999 14:27:46 -0500

At 05:45 PM 1/5/1999 -0000, D. J. Bernstein wrote:
>How exactly is a new implementor supposed to prevent these failures?
>
>Sure, the implementor can test millions of existing domains, but what
>happens when people start setting up longer NS chains next year?
>
>The DNS specifications are inadequate. Domains that comply with BIND's
>undocumented limits aren't guaranteed to work with new implementations.
>Anyone who writes a resolver is threatened with the possibility of
>interoperability disasters. Do you want everyone to copy the BIND code?

Perhaps there should be an RFC recommending reasonable defaults for such
parameters.  A first draft might just start with documenting what BIND does
now, and perhaps in the future as the internet grows, this can be updated.

		--Dean
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
           Plain Aviation, Inc                  [email-masked]
           LAN/WAN/UNIX/NT/TCPIP          http://www.av8.com
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From: Dean Anderson <[email-masked]>
Date: Wed, 06 Jan 1999 20:13:25 -0500

At 03:35 AM 1/7/1999 +1100, Robert Elz wrote:
>    Date:        5 Jan 1999 17:45:17 -0000
>    From:        "D. J. Bernstein" <[email-masked]>
>    Message-ID:  <[email-masked]>
>
>  | How exactly is a new implementor supposed to prevent these failures?
>
>Do you mean the practical failures, or the imaginary theoretical ones?
>
>No reasonable implementation is going to have a problem with any
>NS setup that is actually used in practice, and works.   Similarly,
>none are going to cope with the worst scenarios that can be dreamed
>up as technically possible.

By definition, this is true. But I think the real issue he is getting at is
how does one define "reasonable"?  Suddenly a case appears and your
implementation doesn't work. Is it unreasonable not to work in such a
situation?  How does one answer the question of whether one has a
"reasonable" implementation?

Simply comparing with BIND behavior might not be a satisfactory way of
determining 'reasonableness'.

		--Dean

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From: Randy Bush <[email-masked]>
Date: Thu, 7 Jan 1999 00:33:33 -0800 (PST)

the thread is losing useful content.  if you draft an i-d, please send it.
otherwise, unless a posting on this topic has something new to say other
than insulting others, if you can not refrain from posting it, you may find
i can refrain from approving it.

randy