W3C home > Mailing lists > Public > www-tag@w3.org > June 2012

Misunderstanding documentation protocols

From: Jonathan A Rees <rees@mumble.net>
Date: Fri, 1 Jun 2012 18:38:31 -0400
Message-ID: <CAGnGFM+LP_ce+K3CduNH_z35w2gM2EXGSrMUBBMa9Miey4xQvA@mail.gmail.com>
To: Larry Masinter <masinter@adobe.com>
Cc: "www-tag@w3.org" <www-tag@w3.org>
In April I promised to answer you regarding your misunderstanding of
"Understanding URI Hosting Practice as Support for URI Documentation
Discovery" http://www.w3.org/2001/tag/doc/uddp/ . I think we've been
over most of the terrain in the meantime, but I wanted to try to go
over it again so that it's not left hanging.

If it sometimes sounds like I'm echoing you, that's fine.

Forget about URIs for a moment and just consider, say, English words.
Consider the following ridiculous but illustrative idea: We define a
"dictionary protocol" as follows: take any English word W, form the
URI http://W.com/.well-known/definition , and do a GET of that URI.
The content that comes back will be called (in the terminology of the
protocol spec) a "nominal definition" or ND of the word. The protocol
definition says that the intended use of the protocol is the provision
of (correct) definitions of words; but this would not be a normative
requirement of the spec as there can be no objective test for whether
something is a correct definition of a word.

Suppose a community of agents take this up. Web servers start
providing content at these URIs, and users start using "ND" in what
they say to one another, such as "the ND of the word 'invasive' is not
very good".

Obviously the creation of the protocol won't change the meaning of
messages written in English before the protocol definition was
published, and it will not have a role in the meaning of new messages
where the author of the message is not aware of the protocol. It is
conceivable that agents composing new documents might check the ND of
a word before using it, to decide how to use it; or search NDs to find
words that express some meaning they want to express. But this would
have no bearing on the expectations of senders and receivers in
general. NDs would not be binding on anyone (without their opt-in).

Obviously this system is vulnerable to confusion and attack. An ND
might be quite good and provide excellent documentation that matches
what the word actually means in English - it could be as good as the
OED, it might provide many definitions, corresponding to various
contexts of use, document format contexts, historical periods, etc.,
perhaps even other languages. Such words will have a good "reputation"
and over time the NDs could be treated by some agents or communities
as authoritative. But in general, the content will be up to each
server operator, and is arbitrary.  It could change incompatibly over
time, be wrong or misleading or outdated, source phishing attacks,
appear differently to different readers (conneg-based attacks), etc.
Relying on NDs from unvetted sources would be a bad idea.

When the protocol is in use, the key question is the locus of
accountability when something goes wrong. Is the sender vouching for
the reliability of (or granting authority to) the ND service for the
words (URIs) in their message, or is the receiver only using ND
services as a heuristic for figuring out what the sender *might* have
intended, taking on full responsibility in case the retrieved ND is
not in line what the sender meant? Is it sender beware or receiver
beware? Sender beware has been proposed. It would require opt in from
all senders, past and future, which is impossible. Even if we restrict
discussion to particular formats / contexts such as RDF, this is not
how RDF or any other message format is specified today. The UDDP memo
therefore assumes receiver beware. I tried to make this clear in the
"risks" section, but apparently failed.

I'm not defending FYN, semantic web, or linked data; if anything I'm
trying to expose to the light the architectural problems they elicit.
You seemed to take the composition of the UDDP memo as an endorsement
of its content, and it certainly was not.

... I think it's important to note that FYN is not part of RDF, and
not all uses of RDF suggest it. For example OWL (which has an RDF
binding) doesn't imply FYN for interpreting URIs at all - consulting
the web would actually be incorrect in the general case. The meaning
of every URI, for purposes of the ontology in which it occurs, is
defined locally in the ontology in which it occurs. (Of course it's
nice if URIs are used consistently across all OWL ontologies; but
there's nothing in the spec that requires this.) So I think the
designers of OWL were aware of the weakness of FYN on some level. (OWL
does use web-referring ontology version URIs which act like '#include'
in C, and these affect the identity of an ontology. I suspect that for
ontology version URIs, the community expectation is sender beware, but
this would be an empirical question.)


On Wed, Apr 11, 2012 at 9:53 PM, Jonathan A Rees <rees@mumble.net> wrote:
> Listen, don't answer my previous message as it doesn't address your
> accusations that I subscribe to the incoherent and/or incorrect
> theories that you misattribute to me. I will answer that in due time.
Received on Friday, 1 June 2012 22:39:01 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 22:56:45 UTC