Internet Info 1997 December/Internet_Info_CD-ROM_Walnut_Creek_December_1997.iso/ietf/uri/uri-minutes-93mar.txt

Text File | 1993-05-01 | 11KB | 304 lines

CURRENT_MEETING_REPORT_

Reported by Alan Emtage/BUNYIP

Minutes of the Uniform Resource Identifiers Working Group (URI)

The Uniform Resource Identifiers Working Group held three sessions in
Columbus.  These Minutes are separated on a per-session basis.

Agenda


   o Uniform Resource Locators (URLs) - Session 1
   o Uniform Resource Names (URNs) - Session 2
   o Discussion of Other Necessary Objects - Session 3


Uniform Resource Locators (URLS) - Session 1

In order to try to prevent further confusion it was agreed that the
following terminology would be used:

For all the various UR* objects being discuss, the ``U'' would stand for
``Uniform'' and the ``R'' would stand for ``Resource''.


URL      is Uniform Resource Locator
URN      is Uniform Resource Name
URI      is Unform Resource Identifier (the collective name for UR*)


A discussion of Tim Berners-Lee's current draft on Uniform Resource
Locators (URLs) followed.  The following points were made:


   o It is expected that in the near future character sets other than
     ASCII will need to be addressed.  However in the short run it was
     decided that ASCII would be adequate for the task.  The point was
     made by several European members of the Working Group that while
     other character sets would be necessary, it is important to get the
     current draft out and have the protocols discussed therein
     implemented.  Wording to the effect that this matter has been
     addressed should be incorporated into the current text.  The
     mechanisms defined need to be extensible to allow for expansion in
     this area.

   o The issue of ``fragments'' was raised.  While the current draft
     addresses ``large scale'' objects such as entire files and
     services, it makes no attempt at defining sub-objects (such as a

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  paragraph, word or individual letter in text file).  For example,
  how does one define a ``paragraph'' in a PostScript file, given
  that this is effectively an interpreted language?  The general
  consensus was that we still do not have an adequate understanding
  of the underlying principles involved and that this discussion
  should be pursued on the mailing list.

o The issue of OSI distinguished names in URLs was discussed.  While
  further discussion is probably warranted, consensus held that this
  would probably be too ``heavy'' for the current proposals.

o MIME encodings are also one possible avenue for describing network
  objects.  It was agreed that the Working Group should work closely
  within the framework of existing RFCs for such descriptions.
o It was agreed that the current URL draft should include an example
  URL specification for each access method defined in order to guide
  implementors.

o Again the issue of partial URLs in the current draft was raised.
  It was agreed that while systems may choose to use such constructs
  internally, at no time would they be valid at the inter-system
  interface.  Consensus was reached that stronger warnings need be
  placed in the current draft to that effect.  It was also agreed
  that in the interests of time further discussions of the issue
  should be taken to the mailing list.  The definition of partial
  URLs should also be moved to an appendix of the current document
  since they are not part of the official specification.  Any
  algorithm for determining partial URLs should also be moved to the
  appendix.

o The mechanism for registering new access methods with the Internet
  Assigned Numbers Authority (IANA) should be more prominently placed
  in the current draft.  Also, some mechanism for defining
  experimental access methods should be included.

o Several issues were raised which, it was decided, were better
  suited for the upcoming URN discussion since they fell into that
  domain.

   -  Some form of integrity test was suggested (check digits) for
      URLs.  It was decided that since URLs are inherently transitory
      in nature, that such tests would not be necessary.
   -  Versioning
   -  Security issues
   -  Time to Live (TTLs)


o It is expected that with this input the current draft can be
  submitted for Internet-Draft status within a few weeks following

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     the meeting.


Uniform Resource Names (URNs) - Session 2

Before the meeting Cliff Lynch had posted an overview document to the
mailing list titled ``A Framework for Identifying, Locating, and
Describing Networked Information Resources'' and at the beginning of the
session, he described the major points that the paper contained.

John Kunze had also posted a document entitled ``Resource Citations for
Electronic Discovery and Retrieval'' and made a short presentation about
the paper.

Peter Deutsch made a presentation as to a possible architecture for
URNs.

A ``spirited'' discussion followed as a result.

There was much discussion as to what properties a URN should and should
not have and the resulting fracas was in the best tradition of IETF
``consensus building''.

It was agreed that while some of the underlying data of particular
network objects changed (for example, a video feed), that the URN
associated with such an object would remain essentially the same.
However, the URNs for the underlying data would have to change as the
data changed.

Several suggestions for the type of information to be included in URNs
were discussed and it was decided that a final decision would be made at
the final session.

Discussion of Other Necessary Objects - Session 3

After canvassing several members of the Working Group, the session
started with a short presentation by one of the co-Chairs, Alan Emtage.
It was proposed that the URN have a very simple structure.  In order to
be able to completely distinguish URNs from URLs the following structure
was proposed:


     URN:<ID Authority>:<URS>


The string ``URN'' is part of the structure.  <ID Authority> is the
unique identifier for the issuing authority.  <URS> is the Uniform
Resource String which is unique (as determined by the ID Authority) for
that ID Authority.  No assumptions may be made about the substructure of
the URS which is effectively opaque to any entity other than the ID
Authority.  The ID Authority would be registered with the IANA to ensure
uniqueness.

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This proposal was endorsed and the corresponding document would be
written by Alan Emtage, Jim Fullton and Chris Weider and submitted to
the mailing list as soon as possible.  It is hoped that the document can
become an Internet-Draft at or before the Amsterdam meeting.

A presentation was made by Rob Raisch which suggested some revisions to
the above scheme.

Questions about architecture were raised and it was suggested that the
current draft architecture document from the Integration of Internet
Information Resources (IIIR) Working Group be consulted.

Further discussion illustrated the fact that the combination of URL &
URN would not be sufficient for an effective infrastructure since much
of the data needed by the user to determine desirability of an object
located through a search was not present in these structures.  These
include such things as :


   o Versioning
   o Language
   o Character Sets
   o Representation (eg, PostScript, bitmaps, ASCII etc)
   o A whole array of non-static/non-text attributes


Tim Berners-Lee, John Kunze and Michael Mealling made presentations as
to how to handle this ``meta data'' or ``factoids''.

It was decided that defining the semantics and syntax of these
attributes would take careful work and should be the focus of upcoming
meetings.

Attendees

Harald Alvestrand        [e-mail]
Jules Aronson            [e-mail]
Karl Auerbach            [e-mail]
Paul Barker              [e-mail]
Robert Beer              [e-mail]
Tim Berners-Lee          [e-mail]
Jodi-Ann Chu             [e-mail]
William Chung            [e-mail]
David Conklin            [e-mail]
James Conklin            [e-mail]
Naomi Courter            [e-mail]
John Curran              [e-mail]
Brent Curtiss            [e-mail]
Mark Davis-Craig         [e-mail]
Peter Deutsch            [e-mail]
Thomas DeWitt            [e-mail]
Dale Dougherty           [e-mail]
Alan Emtage              [e-mail]

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Urs Eppenberger          [e-mail]
Roger Fajman             [e-mail]
Jill Foster              [e-mail]
Steven Foster            [e-mail]
Jim Fullton              [e-mail]
Kevin Gamiel             [e-mail]
Joan Gargano             [e-mail]
Greg Gicale              [e-mail]
Deborah Hamilton         [e-mail]
Susan Harris             [e-mail]
Alisa Hata               [e-mail]
Russ Hobby               [e-mail]
Ellen Hoffman            [e-mail]
Susan Horvath            [e-mail]
Inna Il'yasova           [e-mail]
Erik Jul                 [e-mail]
Scott Kaplan             [e-mail]
Michael Khalandovsky     [e-mail]
John Klensin             [e-mail]
Jim Knowles              [e-mail]
Andrew Knutsen           [e-mail]
Edward Krol              [e-mail]
John Kunze               [e-mail]
Ronald Lanning           [e-mail]
Hock-Koon Lim            [e-mail]
Clifford Lynch           [e-mail]
Bruce Mackey             [e-mail]
Samir Malak              [e-mail]
Gary Malkin              [e-mail]
Janet L. Marcisak        [e-mail]
April Marine             [e-mail]
Ignacio Martinez         [e-mail]
Michael Mealling         [e-mail]
Keith Moore              [e-mail]
Jim Naro                 [e-mail]
Mark Needleman           [e-mail]
Clifford Neuman          [e-mail]
Bill Norton              [e-mail]
Masataka Ohta            [e-mail]
Geir Pedersen            [e-mail]
Pete Percival            [e-mail]
Charles Perkins          [e-mail]
Marsha Perrott           [e-mail]
Cecilia Preston          [e-mail]
Robert Raisch            [e-mail]
Joyce K. Reynolds        [e-mail]
Francois Robitaille      [e-mail]
Richard Rodgers          [e-mail]
Charlie Smith            [e-mail]
Jane Smith               [e-mail]
Patricia Smith           [e-mail]
Sue Smith                smiths.es.net
Karen Sollins            [e-mail]
Wayne Tackabury          [e-mail]

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Matt Tuttle              [e-mail]
Ruediger Volk            [e-mail]
Janet Vratny             [e-mail]
Chris Weider             [e-mail]
Les Wibberley            [e-mail]
Richard Wiggins          [e-mail]



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