Subject: DAV:orderingtype Property in the Advanced Collections Spec

From: "Slein, Judith A" <[email-masked]>
Date: Wed, 16 Sep 1998 09:48:20 -0400

At IETF 42 it was suggested that the possible values of the
DAV:orderingtype property (and so also of the Ordered request header) be
changed to the following set:

DAV:unordered -- this collection is not ordered
DAV:custom -- this collection is ordered, but the semantics for its
ordering is not being published
href -- URI identifying the semantics of the ordering

At IETF 42, it was proposed that an href value be treated primarily as
an identifier of the semantics, rather than as a pointer to a location
where a definition of the semantics can be found.   It was suggested
that the specification explicitly discourage clients from dereferencing
the URI.  The rationale for discouraging clients from dereferencing the
URI is that a common practice of dereferencing these URIs could lead to
unexpectedly heavy use of sites where ordering semantics are defined.

My own feeling is that this consequence of dereferencing is unlikely.
The only people likely to look up the semantics are people other than
the owner of the collection who want to add members to it.  The people
who are allowed to do this are likely to be restricted, and are likely
to know the semantics of the ordering anyway.  But for the few cases
where the person adding to the collection does not know the semantics of
the ordering, being able to look up a definition can be extremely
useful.  I am willing to make the change, however, particularly since it
only discourages clients from dereferencing the URI, and does not forbid
doing so.

Judith A. Slein
Xerox Corporation
[email-masked]
(716)422-5169
800 Phillips Road 105/50C
Webster, NY 14580

---

From: Jim Whitehead <[email-masked]>
Date: Wed, 16 Sep 1998 10:29:11 -0700

> to know the semantics of the ordering anyway.

I recommended this change.  My concern was that people might want to express
the ordering in a machine-readable format, and this would then lead to
widespread downloading of the machine-readable ordering semantics from one
URL, overloading this URL.

- Jim