Re: iDNR, an alternative name resolution protocol

Leslie Daigle (leslie@Bunyip.Com)
Wed, 2 Sep 1998 09:27:20 -0400 (EDT)

Date: Wed, 2 Sep 1998 09:27:20 -0400 (EDT)
From: Leslie Daigle <leslie@Bunyip.Com>
To: "Martin J. Duerst" <>
cc: Larry Masinter <>,
In-Reply-To: <>
Message-ID: <>
Subject: RE: iDNR, an alternative name resolution protocol


On Wed, 2 Sep 1998, Martin J. Duerst wrote:
> - A minimum that should be achieved by normalization at the origin;
>   this is mainly to eliminate pure encoding duplicates such as they
>   appear with precomposed/decomposed. At W3C, we are coordinating
>   this work with Unicode; they have already issued a draft on this
>   issue (, on which
>   also comments are welcome.


> - An even larger class of equivalences that would be used e.g. for
>   tools that check for spoofing attempts. This may include things
>   such as wrongly interpreted encodings (e.g. something that is
>   actually Latin-1 instead of UTF-8,...) and almost everything that
>   didn't go into the last item for a particular case.



> - Some larger equivalences that may be offered as "quality of service"
>   (e.g. for the directory/file component and case-insensitivity for
>   many HTTP servers) or may be part of the protocol/scheme/scheme
>   component,... (e.g. case folding for domain names).

My only point is that, where there is "similarity matching", provided
as a user aide, there is loss of "discrimination capability" for
the service provider, and all parties MUST be working from the same rules.

As an obviously-constructed example, let's look at Alain's example
of "du" and "d".  (This is only peripherally about case matching, now,
and more generally about what should be considered matches in fuzzy

A service might use
	    for a customer to see the amount of service usage for the
	    month (measured in hits, if its a search service).
	    for a customer to see the account balance for the month.
	    (I.e., "amount due (month)", as opposed to "amount due (annual)").

As I said, the example is a bit forced, but that's due to my lack of
imagination, not that it's an unrealistic concern.

If we say that "u" and "" (or "U" and "", if I repeat the above
example in all caps) should be considered as matching for URIs, then 
the service provider cannot provide those two as distinct URIs.
The discussion as to whether that is too limiting, entrenches the 
poor support for other languages in Internet technologies,  or is
perfectly acceptable is a separate discussion.  

What would be dangerous, in my opinion, is to NOT make it CLEAR
whether or not these things should match (algorithmically, deterministically),
because the service might legitimately construct a web site using 
these two uri's, serve it reliably using HTTP server of BrandA for years,
switch to HTTP server of BrandB because it provides better performance,
and suddenly wonder why customers are unable to access

and eventually discovering it's because BrandB considers "u" and ""
similar enough to match.  Repeat the experiment for client software,
and cache software and...



    If cats had bumper stickers:                  Leslie Daigle
      "I wake for food."                          Bunyip Information Systems
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