RDFCore Working Group Implementation Report, PR request

$Revision: 1.39 $ of $Date: 2003/12/03 14:43:19 $ by $Author: bmcbride $
see changelog since 7Nov WG decision below.
Brian McBride, Dan Brickley and Eric Miller

Dear W3C Director,


The RDFCore Working Group decided ( 2003-11-07 meeting record in progress) to request that you advance this specification to W3C Proposed Recommendation and commence W3C Advisory Committee review.

A version of this document which may have been updated, possibly with new implementation experience or to reflect the status of the specifications, is linked from the RDFCore overview page.

Titles, Abstracts, and Status

The Working Group has developed the following specification, test materials, and supplementary documentation for RDF:

Summary of Review

Review of the above drafts began drafts of RDF Semantics and RDF Syntax in September 2001 and RDF Schema in April 2002. Remaining parts of the original RDF Model and Syntax specification appeared subsequently in RDF Concepts and Abstract Syntax, supplemented by the RDF Primer.

The working group addressed comments on these drafts on a best-effort basis as it worked thru its list of 60+ issues.

After resolving all of the issues, last call working drafts were published in January 2003 and last call comments were formally addressed. The Working Group made a number of changes in response to these comments, and then issued a second last call in October 2003. Comments on the 2nd last call were also formally addressed.

While the vast majority of the issues were resolved by consensus, three issues with outstanding objections remain: datatypes, XML Literals, and validating RDF.

Implementation Experience and Endorsement

The the RDF Core test case results and the following implementation exprience validate the design and motivates widespread deployment.

Title: Sesame
Contact: Arjohn Kampman Jeen Broekstra
Language: Java
Sesame is an Open Source RDF Schema-based Repository and Querying facility

- Sesame aidministrator nederland bv Home Page

Title: Drive
Contact: Rahul Singh
Language: C#
Drive is an RDF parser written in C# for the .NET platform. Its fully compliant with the W3C RDF syntax specification and is available as open source under the terms of the GNU LGPL license.

- Drive Home Page

Title: Raptor RDF Parser Toolkit
Contact: Dave Beckett
Language: C
Raptor is a free software/Open Source C library that parses RDF syntaxes such as RDF/XML and N-Triples into RDF triples.

Raptor was designed to work closely with the Redland RDF library (RDF Parser Toolkit for Redland) but is entirely separate. It is a portable library that works across many POSIX systems (Unix, GNU/Linux, BSDs, OSX, cygwin, win32). Raptor has no memory leaks and is fast.

- Raptor Home Page

Title: TAP
Contact: R.V. Guha, Rob McCool
TAP is an application framework for Building the Semantic Web. TAP's goals are to enable the Semantic Web by providing some simple tools that make the web a giant distributed Database. TAP is open source development effort by R.V. Guha (IBM) and Rob McCool (Stanford) which provide a set of protocols and conventions that create a coherent whole of independantly produced bits of information, and a simple API to navigate the graph. Local, independantly managed knowledge bases can be aggegated to form selected centers of knowledge useful for particular applications.

- TAP - An Application Framework for Building the Semantic Web

Title: Redfoot
Contact: Daniel Krech
Language: Python
Redfoot is a program for managing and sharing RDF information using RDFLib. Redfoot is currently geared mostly to the developer, but is shifting in the direction of the end user.

- Redfoot Home Page

Title: Euler
Contact: Jos De Roo
Language: C#
EulerSharp is an inference engine supporting logic based proofs. It is a backward-chaining reasoner enhanced with Euler path detection and will tell you whether a given set of facts and rules supports a given conclusion. It is interoperable with W3C Cwm. - Sourceforge EulerSharp project

Title: ARP Another RDF Parser
Contact: Jeremy Carroll
Language: Java
The Jena RDF/XML Parser

- ARP Home Page

Title: Joseki
Contact: Andy Seaborne
Language: Java
Joseki is a server for publishing RDF models on the web. Models have URLs and they can be accessed by query using HTTP GET. Joseki is part of the Jena RDF toolkit. Joseki provides a coarse-grained web API that is based on extracting a subgraph from the published RDF. The extracted RDF can then be processed locally with the fine-grained API provided by Jena.

- Joseki Home Page

Title: PerlRDF
Contact: info@gingerall.com
Language: Perl
PerlRDF is a Perl implementation of RDF storage, parser and serializer. The storage's functionality is store, delete and query statements, where query means ask about existence of statements conforming a given mask (subject, predicate, object). Three storages are available - in memory, file (DB_File) and DBMS (PostgreSQL). The parser makes use of XML::Parser and supports full RDF/XML syntax including changes from 2003. The serializer tries to preserve anonymous nodes and to compact xml by grouping statements with common subject. Besides the basic querying, there is a resource-centric query language implemented. RDF::Core also provides a basic object oriented interface for the RDF Schema manipulation.

- PerlRDF Home Page

Title: IsaViz
Contact: Emmanuel Pietriga
Language: Java
IsaViz is a visual environment for browsing and authoring RDF models represented as graphs.

- IsaViz Home Page

Title: RDFlib
Contact: Daniel Krech
Language: Python
RDFLib is a Python library for working with RDF, a simple yet powerful language for representing information. The library contains an RDF/XML parser/serializer, a TripleStore, an InformationStore and various store backends (InMemory, SleepyCat BTree, ZODB BTree).

- RDFLib Home Page

Title: Wilbur
Contact: Ora Lassila
Language: Lisp
Wilbur is a toolkit for writing RDF-enabled software. Wilbur is written in CLOS, and includes an RDF parser, a DAML parser, an XML parser, an API for managing "RDF data", and a simple HTTP client; it also includes a simple (and at this point experimental) frame system on top of RDF & DAML.

- Wilbur: Nokia's RDF Toolkit for CLOS

Title: Jena2 - A Semantic Web Framework
Contact: Brian McBride
Language: Java
Jena is a Java framework for building Semantic Web applications. It provides a programmatic environment for RDF, RDFS and OWL, including a rule-based inference engine. Jena is open source and grown out of work with the HP Labs Semantic Web Programme.

- Jena Sourceforge project page

Title: BrownSauce RDF Browser
Contact: Damian Steer
Language: Java
There is RDF data all over the place, in XML documents and sources like databases. Getting all that data is impractical, and would be unreadable (to say the least). So BrownSauce is an attempt to make something which can browse that information.

BrownSauce breaks the problem into two parts: coarse-graining (breaking the data down into usable chunks, like 'information about person X) and aggregation (making those chunks from multiple sources). The first part is done, and users can browse more than one source using rdfs:seeAlso references. Aggregation is currently being worked on.

BrownSauce runs as a local http server, or can be added to a java web application server like Tomcat or Jetty. The current interface is HTML and can be styled using CSS (the HTML is marked up using classes relating to the RDF). Other interfaces should be simple to implement.

- BrownSauce RDF Browser Home Page

Title: Intellidimension's RDF Gateway
Contact: Geoff Chappell
RDF Gateway is a platform designed from the ground up for the Semantic Web. It's an application server, a web server, and a deductive RDF database server all in one. RDF Gateway offers a familiar programming model and language that enables today's web and database developers to quickly begin creating Semantic Web applications that can be easily deployed to workstations and servers running RDF Gateway.

- RDF Gateway Home Page

Title: RAP - RDF API for PHP
Contact: Chris Bizer
Language: PHP
RDF API for PHP is a pure PHP software package for parsing, manipulating and serializing RDF models.

- RAP - RDF API for PHP Home Page

Title: Swish
Contact: Graham Klyne
Language: Haskell

Swish is a toolkit for Semantic Web inference written in Haskell. It is being developed to support simple Semantic web applications, through the creation of generic and specific command-line RDF inference programs, with a particular view to inclusion of datatype-aware reasoning. Datatype reasoning is seen as a way for controlled inclusion of additional processing capabilities into a simple RDF inference process.

The current released version of Swish contains a Notation3 parser, together with graph comparison and merging capabilities. A framework for implementing various kinds of rules, including datatype constraint reasoning, is at an advanced state of development, and is hoped to be released before the end of 2003.

It is intended that this framework can be used as a testbed for exploring RDF inference features required to build real applications, a motivating example of which is a network access control configuration experiment undertaken as part of the SWAD-E project (cf. http://www.ninebynine.org/SWAD-E/Intro.html#HomeNetAccessDemo).

- ANNOUNCE: SW Inferencing Skeleton in Haskell (Swish), Graham Klyne, Fri, 06 Jun 2003


CVS log of changes since 7Nov WG decision:

$Log: 20030331-advance.html,v $
Revision 1.39  2003/12/03 14:43:19  em
updated to make xhtml valid

Revision 1.38  2003/11/17 10:15:28  bmcbride
Added reference to WG version of request

Revision 1.37  2003/11/17 10:01:08  bmcbride
updated doc status

Revision 1.36  2003/11/14 18:52:39  bmcbride
Removed draft status and final @@'s

Revision 1.34  2003/11/13 20:24:28  em
added hr

Revision 1.33  2003/11/13 20:23:18  em
style changes

Revision 1.32  2003/11/13 20:22:00  em
style changes

Revision 1.31  2003/11/13 20:18:01  em
updated to wrap up impl section

Revision 1.30  2003/11/13 20:16:49  em
updated to wrap up impl section

Revision 1.29  2003/11/13 20:12:24  em
updated to wrap up impl section

Revision 1.28  2003/11/13 20:08:37  em
updated to wrap up impl section

Revision 1.27  2003/11/13 19:44:26  em
updated to fix merge problems in summary of review section

Revision 1.26  2003/11/13 19:41:25  em
updating implementation section

Revision 1.25  2003/11/12 22:33:58  connolly
rewrote summary of review, noting when 1st WDs went out,
telling good news about lots of issues resolved by
left an @@ to represent the pending responses to LC2 comments

Revision 1.24  2003/11/12 21:49:48  connolly
punted pending edits on test, concepts to Brian
completed this pass of the titles section

Revision 1.23  2003/11/12 18:54:32  connolly
cited current primer, pending edits

Revision 1.22  2003/11/12 18:07:06  connolly
cited semantics LC2, editor's draft, noted pending changes

Revision 1.21  2003/11/12 15:39:27  connolly
finished citing schema for request-for-PR purposes; noted minor changes pending

Revision 1.20  2003/11/12 15:23:32  connolly
cited syntax spec: 10Oct LC version, editors draft, changes

Revision 1.19  2003/11/12 14:49:48  connolly
link WG decision, start change log