2. LC and the W3C: History b Attended two W3C Workshops Indexing/Distributed Search - 1996Indexing/Distributed Search - 1996 Query Language - 1998Query Language - 1998 b Joined W3C April 1999 b Attended 2 AC Meetings - November 1999November 1999 May 2000May 2000

4. Why should libraries care? b Libraries have a big stake in several activity areas. b Libraries have significant expertise to offer in several areas e.g.: metadatametadata identifiersidentifiers character setscharacter sets information retrievalinformation retrieval

5. LC’s interest in W3C b HTML b Stylesheets b XML b Metadata b graphics b Character Sets b Identifiers b Information Retrieval/Query b Accessibility b Digital Signatures b IPR

6. LC’s interest in W3C - Categories b As a content provider b Copyright Office b Nat. Library for Blind and Physically Handicapped b Library/part of library community

7. LC’s interest in W3C b As a content provider HTMLHTML StylesheetsStylesheets XMLXML graphicsgraphics b Copyright Office Digital SignaturesDigital Signatures IPRIPR b NLSBPH AccessibilityAccessibility

8. Library-related interests b Metadata b Character Sets b Identifiers b Information Retrieval/Query b Accessibility

9. Proposal for URI Activity b Proposed at November 1999 AC Meeting Dan LaLiberte, ChairDan LaLiberte, Chair b Proposal seemed well-received (certainly, by LC) b Proposal withdrawn abruptly, by Tim Berners-Lee, January 2000 b LC was not pleased.

10. URIs (background) b b URI: “uniform resource identifier” b Originally, b Originally, a generalization of: URL (uniform resource locator), URN (uniform resource name), URC (uniform resource citation), and potentially others, b b but mainly, URL and URN

11. The difference (in theory) between URL and URN: b b a URL is bound to a location when resource moves, url changes b b a URN is a name thus location independent, and, in theory, persistent (whatever “persistent” means)

12. The Other View b b Distinction between URL and URN is artificial b b Both terms should be abolished and replaced by “URI” b b thus all identifier “schemes” would be URI schemes (even “http”) and no prefix would be necessary (URL, URN, or even URI).

13. Reasoning b b Original URI philosophy: URLs were a short-term solution and URNs long-term. URL would be a temporary identification mechanism until a location-independent, persistent identifier was developed, the URN. b b Now it seems: URNs won’t be any more persistent than URLs – persistence is a social problem, not a technical problem

14. Two Views: b URL http:http: ftp:ftp: z39.50 z39.50 ……..…….. b URN nbn:nbn: hdl:hdl: b URC? b Http: b ftp: b hdl: b tv: b urn: nbn: hdl:

15. The Problem b LC frustrated with the pace of development and lack of progress b no coherent URI infrastructure b no resolution framework

16. URI Issues b resolution b registration b proliferation b persistence b Degree of centralization b referral/re-direction b support for human readable - and legacy- identifiers b separation of metadata from identifier b Unicode support

17. Primary URI Issues b Registration “what URI is used for ISBN?”“what URI is used for ISBN?” b resolution “how would it be resolved?”“how would it be resolved?” b proliferation URI-scheme evolution must be sufficiently manageable that browsers can implement a core set of schemes so users won't be constantly downloading plug-ins for different schemes.URI-scheme evolution must be sufficiently manageable that browsers can implement a core set of schemes so users won't be constantly downloading plug-ins for different schemes. b persistence

18. “Persistence” it means different things to different people b Location-independence when the resource moves, the identifier remains the samewhen the resource moves, the identifier remains the same b uniqueness only one identifier for a given resourceonly one identifier for a given resource b permanence once assigned to a resource, the resource will exist foreveronce assigned to a resource, the resource will exist forever b unambiguous - ness once assigned to a resource, that identifier may never be assigned to another resourceonce assigned to a resource, that identifier may never be assigned to another resource

19. LC’s View b P ersistence is not a technical problem - it’s a social problem, and a problem that neither the IETF nor the W3C is equipped to solve. b Responsibility for ensuring that URIs( continue to) resolve to the appropriate content should lie with the entity managing that content. b Different naming schemes will be used with different semantics and administrative policies. Resolvers for a naming scheme will be responsibility of the body administering the scheme.

20. What’s Missing? b A framework permitting an evolution of URI schemes sufficiently manageable that browsers can implement a core set of schemes so users won't be constantly downloading plug-ins for different schemes. b More to the point for the library world: library automation vendors need to know what schemes they need to support.

21. What’s Missing? (continued) b A deployed mechanism for directing resolution requests to the appropriate resolver. b An effective technical infrastructure allowing identifiers to be recognized and handled by browsers. b A single document -- for example, a W3C technical report or, preferably, a Recommendation -- that ties all the information together coherently, and recommends revision where appropriate.

23. What is a URI? Two Views: b URL http:http: ftp:ftp: z39.50 z39.50 ……..…….. b URN nbn:nbn: hdl:hdl: b URC? b Http: b ftp: b hdl: b tv: b urn: nbn: hdl:

24. New URI Interest Group b New W3C Proposal for a URI Interest Group within the Architecture Domainwithin the Architecture Domain b to: “Build and maintain shared understanding around URIs technology and specifications” b mission: to be responsive to the needs of the W3C membership and WGs for information about URI technology.

25. LC’s interest in WAI b LC is a Federal Agency b LC includes NLSBPH (National Library Service for the Blind and Physically Handicapped) Digital talking booksDigital talking books Web-brailleWeb-braille

26. Information Retrieval b XML and Protocols Z39.50?Z39.50? b Z39.50/RDF integration an RDF representation of Z39.50 attribute sets?an RDF representation of Z39.50 attribute sets? align RDF and Z39.50 data models?align RDF and Z39.50 data models? b XML query language a Z39.50 query type?