1 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Webvise: Browser and Proxy Support for Open Hypermedia Structuring Mechanisms on the WWW Kaj Grønbæk, Lennert Sloth, & Peter Ørbæk InterMedia - Aarhus University of Aarhus

2 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia …or addressing the challenge: “- if you notice a connection make a link!” (Tim Berners-Lee, this mornings keynote)

3 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Plan What is open hypermedia? The Webvise open hypermedia service for the Web The Webvise client for authoring and browsing The Webvise proxy service for read-only browsing (Demo) Application domains Work in progress Status and conclusion

4 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Link object I medfør af § 93, stk. 2 i bekendtgørelse nr af 18. december 1995 om levnedsmiddelhygiejne og egenkontrol m.v. og § 20, stk. 2 i bekendtgørelse nr. 931 af 6. december 1995 om materialer og genstande bestemt til at komme i berøring med levnedsmidler fastsættes: Ændringsbekendtgørelse nr af 18. juli 1997 om..... Open hypermedia for the WWW Users may create their own structures (links, collections, annotations etc.) on the Web Structures (contexts) are stored in separate databases Many layers of structure on top of the same Web documents Users may apply one or more layers at a time

5 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Combining structure and content Content: Arbitrary Web pages Structures: links, notes, guided tours Webvise Client or Proxy Combined HTML, etc. (Contexts of structure for various subject areas)

6 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Open hypermedia basic architecture Uses standard on-the- wire protocols (TCP/IP and HTTP) OHP: Open Hypermedia Protocol - standards proposal put forward by OHSWG ( Standard on-the-wire operation format: XML Web server Office apps. Applications Structure Server Hyperstore OHP Office apps. Web Browsers MS IENS C NavLets Webvise HSP JDBC/ ODBC Proxy Web server

7 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Datamodel for open hypermedia structures Extensible model Open for new structuring mechanisms Open for new locating methods Open for collaboration

8 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia LocSpecs: Locating segments of data A locSpec is used to specify a certain location within a node’s content LocSpecs use several attributes to hold location information: Reference, Selection, Selection context, Axis specification. In most cases one of these attributes is sufficient Example: Text document Reference: a bookmark ID or a HTML target name Selection: the text of the span to search for Selection context: some surrounding text Axis: a position, such as start position, and stop position Detecting and repairing inconsistencies

9 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Examples of open hypermedia protocol (OHP) operations NewLink: request = (MessageHeader, (endpoint)*, linkType, HyperSpace) Ex.: webBrowserViaHyperviseCl 0 0 Announcements 3 v1.0 baseUrl [url] ameName][/frameName] frameName MAINWINDOW docTitle DAIMI Announcements no graphics. Announcements: response = (LinkId, (EndPointId)*) Ex.: FollowLink: request = (MessageHeader, contentSpec, locSpecList, direction) Ex.: webBrowserViaHyperviseCl Announcements 3 response = (ResponseCode, endpointList)

10 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia DEMO

11 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Webvise user interface

12 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Internet Explorer extension Entries added to the context menu (right button menu) COM communication with Webvise

13 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Proxy server link decoration Readers only interface Visual indication on top of augmented pages

14 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia MS Office integrations Word and Excel extended with menu and toolbar Supports seamless integration of local documents and Web documents COM communication with Webvise

15 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Application domains Works best with stable sources, such as: Digital libraries Document repositories on intranets Law services Specific examples: Agricultural advisory service help farmers in understanding environmental directions and laws published on governmental servers. Digital library usage in student projects Site-Reviews Journalist publishing Internet-based news sites

16 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Work in progress: Collaboration Support Collaboration on documents is coordinated by means of Locking Event notification Versioning A variety of modes for coupling users Uncoupled Loosely coupled Tightly coupled

17 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Work in progress: Link types Types are used to distinguish among links with different semantic meaning Examples: Teachers may use link types such as "introductory", "experienced", and "advanced" to distinguish sources based on the knowledge required to read them. They may discuss the quality of the sources, by introducing link types such as "recommend as primary reading", "recommend as background reading", "useless" etc. The teachers may use the type mechanisms to generate filtered browsers, queries etc.

18 Grønbæk, Sloth & ØrbækWWW8 - Webvise open hypermedia Conclusion and Status Project undertaken in cooperation with TeleDanmark Internet - the biggest Danish Internet service provider Stable prototypes being used for pilot experiments Shares infrastructure with other services Ariadne guided tour system (presented at WWW7) Mimicry system for linking in time-based media (also at WWW8) Potentials for standardization of Internet protocols and datamodel for hypermedia based on external structures Potential integrations with WebDav mechanisms for full blown authoring support Prototype accessible from