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-
-
- [from clifford lynch via brewster kahle]
-
- The Coalition for Networked Information
- Architectures & Standards Working Group
-
- Workshop on ID and Reference Structures
- for Networked Information
-
- There is an increasingly urgent need to develop working
- standards for referencing networked information objects.
- This has a wide range of applications, including links from
- MARC records to source material, references from courseware
- to published material in electronic form, networked
- hypertext pointers, and digital document IDs of the sort
- used in the Wide Area Information Server (WAIS) system.
- Many projects underway today need these types of
- identifiers, and a number of efforts have developed ad-hoc
- solutions so that they can progress. Unfortunately, the
- proliferation of these ad-hoc solutions is a major barrier
- to interoperability.
-
- Responding to this need, the Coalition for Networked
- Information's Architectures and Standards Working Group is
- initiating an effort to develop such a working standard, or
- agreement. One outcome of this work may be a draft
- specification that is forwarded to standards-making bodies
- such as the National Information Standards Organization for
- consideration as the basis of an actual standard. In
- addition, the resulting specification may be submitted to
- the Internet Engineering Task Force for consideration as a
- draft Request for Comment (RFC).
-
- I propose the following process to reach agreement. I am
- distributing this announcement, which includes a number of
- assumptions towards such a specification; redistribution is
- encouraged. Discussion can be carried out electronically on
- the new LISTSERV mailing list that has been set up for the
- Architectures and Standards Working Group, which you can
- subscribe to by sending a mail message in the form
-
- SUB CNI-ARCH yourname
-
- to
-
- LISTSERV@UCCVMA.BITNET
-
- Barring the unlikely event that rapid and full agreement on
- the specification is reached through electronic discussion,
- CNI will sponsor a one-day invitational meeting in early
- November (date and place to be determined). If you have a
- strong interest in this topic and feel you should attend the
- meeting, contact me either by electronic mail
- (CALUR@UCCMVSA.BITNET or CALUR@UCCMVSA.UCOP.EDU) or by
- telephone (510) 987-0522 to have your name added to the
- invitation list.
-
- Aspects of the problem that need to be addressed include
- those below, which I have listed along with some assumptions
- (all subject to question) to provide a starting point for
- our discussions. I do not claim that this list is complete;
- look for areas overlooked as well as react to those
- mentioned. Many people have contributed ideas that appear in
- the list below, but I must make special note of the
- contributions of Brewster Kahle of Thinking Machines and his
- excellent document "Document Identifiers, or International
- Standard Book Numbers for the Electronic Age" (5/9/90).
-
- 1. The need for identifiers, as distinct from location
- information. This is best handled by a number (much like an
- ISSN or ISBN), but the system must accomodate multiple
- number-assigning agencies. Thus, the identifier is proposed
- as <numbering-authority>,<identifier> where numbering
- authorities are registered.
-
- 2. The pointers must be representable as an ASCII string to
- facilitate inclusion in a wide range of material, including
- documents and electronic mail.
-
- 3. Location information must support multiple Locations for
- the document, including the "location of record" and one or
- more redistribution centers, local caches, etc. The means of
- specifying a location should be sufficiently general to span
- at least the set of networks covered under the Internet
- Domain Naming system (DNS).
-
- 4. Objects may be retrieved by a variety of access
- mechanisms from servers, including FTP, LISTSERV, Z39.50,
- and perhaps FTAM and SQL-based database access, as well as
- requests for paper copies. The location information should
- be sufficiently general to include information about these
- different types of access techniques, and extensible to
- include new access methods that may develop in future.
-
- 5. Perhaps the location identifier should include some
- information about the format and size of the object; on the
- other hand, perhaps it should not. Discussion?
-
- 6. It should be possible to further qualify a reference to a
- "sublocation" within an object (which would have meaning
- only to the server that houses it). This is needed, for
- example, for hypertext-type links. Such a sublocation might
- be the 25th paragraph of a text, for a hypertext-type
- pointer.
-
- 7. Indirection should be supported. In other words, one
- should be able to format the location as the name of a
- server that can be passed the identifier and which would
- return location information. The protocol mechanism(s) for
- doing this need to be specified as well.
-
- 8. While full rights and permissions data would seem to be
- outside the scope of such a pointer, it might be useful to
- include at least some basic information. This might be an
- indication that the object is not copyrighted and can be
- freely distributed, that it is copyrighted but can be freely
- distributed, that it can be redistributed for noncommercial
- use, or that restrictions apply to redistribution. Also, it
- might make sense to include a pointer of some sort (an
- e-mail address? a host address?) for further information
- about rights.
-
- 9. Perhaps there might be some type of checksum that can be
- calculated on the retrieved object to ensure that the
- pointer and the object have not gotten out of synch?
-
-
-
-