Kingsley Uyi Idehen's Weblog

In response to the "Semantic Web Technology" application classification scheme espoused by ReadWriteWeb (RWW), emphasized in the post titled: Where are all the RDF-based Semantic Web Apps?, here is my attempt to clarify and reintroduce what OpenLink Software offers (today) in relation to Semantic Web technology.

From the RWW Top-Down category, which I interpret as: technologies that produce RDF from non RDF data sources. Our product portfolio is comprised of the following; Virtuoso Universal Server, OpenLink Data Spaces, OpenLink Ajax Toolkit, and OpenLink Data Explorer (which includes ubiquity commands).

Virtuoso Universal Server functionality summary:

1. Generation of RDF Linked Data Views of SQL, XML, and Web Services in general
2. Deployment of RDF Linked Data
3. "On the Fly" generation of RDF Linked Data from Document Web information resources (i.e. distillation of entities from their containers e.g. Web pages) via Cartridges / Drivers
4. SPARQL query language support
5. SPARQL extensions that bring SPARQL closer to SQL e.g Aggregates, Update, Insert, Delete Named Graph support (i.e. use of logical names to partition RDF data within Virtuoso's multi-model dbms engine)
6. Inference Engine (currently in use re. DBpedia via Yago and UMBEL)
7. Host and exposes data from Drupal, Wordpress, MediaWiki, phpBB3 as RDF Linked Data via in-built support for PHP runtime
8. Available as an EC2 AMI
9. etc..

OpenLink Data Spaces functionality summary:

1. Simple mechanism for Linked Data Web enabling yourself by giving you an HTTP based User ID (a de-referencable URI) that is linked to a FOAF based Profile page and OpenID
2. Binds all your data sources (blogs, wikis, bookmarks, photos, calendar items etc. ) to your URI so can "Find" things by only remembering your URI
3. Makes your profile page and personal URI the focal point of Linked Data Web presence
4. Delivers Data Portability (using data access by value or data access by reference) across data silos (e.g. Web 2.0 style social networks)
5. Allows you make annotations about anything in your own Data Space(s) on the Web without exposure to RDF markup
6. A Briefcase feature that provides a WebDAV driven RDF Linked Data variant of functionality seen in Mac OS X Spotlight and WinFS with the addition of SPARQL compliance
7. Automatically generates RDFa in its (X)HTML pages
8. Blog, Wiki, WebDAV File Server, Shared Bookmarks, Calendar, and other applications that look and feel like Web 2.0 counterparts but emitt RDF Linked Data amongst a plethora of data exchange formats
9. Available as an EC2 AMI
10. etc..

OpenLink Ajax Toolkit functionality summary:

1. Provides binding to SQL, RDF, XML, and Web Services via Ajax Database Connectivity Layer (you only need an ODBC, JDBC, OLE-DB, ADO.NET, XMLA Driver, or Web Service on the backend for dynamic data access from Javascript)
2. All controls are Ajax Database Connectivity bound (widgets get their data from Ajax Database Connectivity data sources)
3. Bundled with Virtuoso and ODS installations.
4. etc.

OpenLink Data Explorer functionality summary

1. Distills entities associated with information resource style containers (e.g. Web Pages or files) as RDF Linked Data
2. Exposes the RDF based Linked Data graph associated with information resources (see the Linked Data behind Web pages)
3. Ubiquity commands for invoking the above
4. Available as a Hosted Service or Firefox Extension
5. Bundled with Virtuoso and ODS installations
6. etc.

Note:

Of course you could have simply looked up OpenLink Software's FOAF based Profile page (*note the Linked Data Explorer tab*), or simply passed the FOAF profile page URL to a Linked Data aware client application such as: OpenLink Data Explorer, Zitgist Data Viewer, Marbles, and Tabulator, and obtained information. Remember, OpenLink Software is an Entity of Type: foaf:Organization, on the burgeoning Linked Data Web :-)

Related

• Linked Data Planet Keynote (RDFa based remix edition)
• On The Cusp: A Global Review of the Semantic Web Industry.

A new release of Virtuoso is now available in both Open Source and Commercial variants. The main features and Enhancements associated with this release include:

* 64-bit Integer Support

* RDF Sink Folders for WebDAV - enabling RDF Quad Store population by simply dropping RDF files into WebDAV or via HTTP (meaning you can use CURL as an RDF in put mechanism for instance)

* Additional Sponger Cartridges from Audio binary files (i.e ID3 tag extraction and Music Ontology mapping which exposes the fine details of music as RDF based Structured Data; one for the DJs & Remixers out there!)

* New Sponger Cartridges for Facebook, Freebase, Wikipedia, GRDDL, RDFa, eRDF and more

* Support for PHP 5.2 runtime hosting (Virtuoso is a bona fide deployment platform for: Wordpress, MediaWiki, phpBB, Drupal etc.)

* Enhanced UI for managing RDF Linked Data deployment (covering Multi Homed domains, Virtual Directories associated with URL-rewrite rules

* Demonstration Database includes SQL-RDF Views & SQL Table samples for the THALIA Web Data Integration benchmark and test-suite

* Tutorial Application includes Linked Data style SQL-RDF Views for the Northwind SQL DBMS schema (which is the same as the standard Virtuoso demo atabase schema)

* SQL-RDF Views implementation of the TPC-D benchmark (Yes, we can run this grueling SQL benchmark via RDF views of SQL Data!)

* A new Amazon EC2 Image for Virtuoso that enables you to instantiate a fully configured instance comprising the Virtuoso core, OpenLink Data Spaces platform and the OpenLink Ajax Toolkit (OAT) (we now have bona fide Data Spaces in the Clouds as an addition to the emerging Semantic Data Web mesh).

Download Lnks:

* Open Source Edition

* Commercial Edition

Ivan Herman just posted another nice example of practical RDFa usage in a blog post titled: Yet Another RDFa Proccessor. In his post, Ivan exposes a URI for his FOAF-in-RDFa file.

Since I am aggressively tracking RDFa developments, I decided to quickly view Ivan's FOAF-in-RDFa file via the OpenLink RDF Browser. The full implications are best understood when you click on each of the Browser's Tabs -- each providing a different perspective on this interesting addition to the Semantic Data Web (note: the Fresnel Tab which demonstrates declarative UI templating using N3).

What's Going on Here?

The OpenLink RDF Browser is a Rich Internet Application built using OAT (OpenLink Ajax Toolkit). In my case, I am deploying the RDF Browser from a Virtuoso instance, which implies that the Browser is able to use the Virtuoso Sponger Middleware (exposed as a REST Service at the Virtuoso instance endpoint: /proxy); which includes an RDFa Cartridge comprised of a metadata extractor and an RDF Schema / OWL Ontology mapper. That's it!

OpenLink Software are pleased to announce release 2.6 of the OpenLink AJAX Toolkit (OAT).

New Semantic Data Web related features and enhancements include:

* A Javascript-based Fresnel processor enabling declarative RDF-based display templates for RDF Data Sources

* An XSLT template for generating HTML pages from the Fresnel processor's XML output

* Interactive Query Builder for SPARQL (iSPARQL). This version of the iSPARQL application includes support for INSERTs and DELETEs

* Enhanced Javascript-based N3/Turtle parser

* New Navigator viewer panel for RDF Browser.

*Project Home Page

*Source Code

*Live Features Demonstrations.

Now that broader understanding of the Semantic Data Web is emerging, I would like to revisit the issue of "Data Spaces".

A Data Space is a place where Data Resides. It isn't inherently bound to a specific Data Model (Concept Oriented, Relational, Hierarchical etc..). Neither is it implicitly an access point to Data, Information, or Knowledge (the perception is purely determined through the experiences of the user agents interacting with the Data Space.

A Web Data Space is a Web accessible Data Space.

Real world example:

Today we increasing perform one of more of the following tasks as part of our professional and personal interactions on the Web:

1. Blog via many service providers or personally managed weblog platforms
2. Create Event Calendars via Upcoming.com and Eventful
3. Maintain and participate in Social Networks (e.g. Facebook, Orkut, MySpace)
4. Create and Participate in Discussions (note: when you comment on blogs or wikis for instance, you are participating in, or creating, a conversation)
5. Track news by subscribing to RSS 1.0, RSS 2.0, or Atom Feeds
6. Share Bookmarks & Tags via Del.icio.us and other Services
7. Share Photos via Flickr
8. Buy, Review, or Search for books via Amazon
9. Participates in auctions via eBay
10. Search for data via Google (of course!)

John Breslin has nice a animation depicting the creation of Web Data Spaces that drives home the point.

Unfortunately, what isn't as obvious to many netizens, is the fact that each of the activities above results in the creation of data that is put into some context by you the user. Even worse, you eventually realize that the service providers aren't particularly willing, or capable of, giving you unfettered access to your own data. Of course, this isn't always by design as the infrastructure behind the service can make this a nightmare from security and/or load balancing perspectives. Irrespective of cause, we end up creating our own "Data Spaces" all over the Web without a coherent mechanism for accessing and meshing these "Data Spaces".

Data Spaces on the Web that provide granular access to RDF Data.

Short History

In anticipation of this the "Web Data Silo" challenge (an issue that we tackled within internal enterprise networks for years) we commenced the development (circa. 2001) of a distributed collaborative application suite called OpenLink Data Spaces (ODS). The project was never released to the public since the problems associated with the deliberate or inadvertent creation of Web Data silos hadn't really materialized (silos only emerged in concreted form after the emergence of the Blogosphere and Web 2.0). In addition, there wasn't a clear standard Query Language for the RDF based Web Data Model (i.e. the SPARQL Query Language didn't exist).

Today, ODS is delivered as a packaged solution (in Open Source and Commercial flavors) that alleviates the pain associated with Data Space Silos that exist on the Web and/or behind corporate firewalls. In either scenario, ODS simply allows you to create Open and Secure Data Spaces (via it's suite of applications) that expose data via SQL, RDF, XML oriented data access and data management technologies. Of course it also enables you to integrates transparently with existing 3rd party data space generators (Blogs, Wikis, Shared Bookmrks, Discussion etc. services) by supporting industry standards that cover:

1. Content Publishing - Atom, Moveable Type, MetaWeblog, Blogger protocols
2. Content Syndication Formats - RSS 1.0, RSS 2.0, Atom, OPML etc.
3. Data Management - SQL, RDF, XML, Free Text
4. Data Access - SQL, SPARQL, GData, Web Services (SOAP or REST styles), WebDAV/HTTP
5. Semantic Data Web Middleware - GRDDL, XSLT, SPARQL, XPath/XQuery, HTTP (Content Negotiation) for producing RDF from non RDF Data ((X)HTML, Microformats, XML, Web Services Response Data etc).

Thus, by installing ODS on your Desktop, Workgroup, Enterprise, or public Web Server, you end up with a very powerful solution for creating Open Data access oriented presence on the "Semantic Data Web" without incurring any of the typically assumed "RDF Tax".

Naturally, ODS is built atop Virtuoso and of course it exploits Virtuoso's feature-set to the max. It's also beginning to exploit functionality offered by the OpenLink Ajax Toolkit (OAT).

Frederick Giasson penned an interesting post earlier today that highlighted the RDF Middleware services offered by Triplr and the Virtuoso Sponger

Some Definitions (as per usual):

RDF Middleware (as defined in this context) is about producing RDF from non RDF Data Sources. This implies that you can use non RDF Data Sources (e.g. (X)HTML Web Pages, (X)HTML Web Pages hosting Microformats, and even Web Services such as those from Google, Del.icio.us, Flickr etc..) as Semantic Web Data Source URIs (pointers to RDF Data).

In this post I would like to provide a similar perspective on this ability to treat non RDF as RDF from RDF Browser perspective.

First off, what's an RDF Browser?

An RDF Browser is a piece of technology that enables you to Browse RDF Data Sources by way of Data Link Traversal. The key difference between this approach and traditional browsing is that Data Links are typed (they possess inherent meaning and context) whereas traditional links are untyped (although universally we have been trained to type them as links to Blurb in the form of (X)HTML pages or what is popularly called "Web Content".).

There are a number of RDF Browsers that I am aware off (note: pop me a message directly of by way of a comment to this post if you have a browser that I am unaware of), and they include (in order of creation and availability):

1. Tabulator
2. DISCO - Hyperdata Browser
3. OpenLink Ajax Toolkit's RDF Browser (a component of the OAT Javascript Toolkit)

Each of the browsers above can consume the services of Triplr or the Virtuoso Sponger en route to unveiling a RDF Data that is traversable via URI dereferencing (HTTP GETing the data exposed by the Data Pointer). Thus you can cut&paste the following into each of the aforementioned RDF Browsers:

1. Triplr's RDF Data (Triples) extractions from Dan Connolly's Home Page
2. The Virtuoso Sponger's RDF Data (Triples) extractions from Dan Connolly's Home Page

Since we are all time challenged (naturally!) you can also just click on these permalinks for the OAT RDF Browser demos:

1. Permalink for Triplr's RDF Data (Triples) extractions from Dan Connolly's Home Page
2. Permalink for the Virtuoso Sponger's RDF Data (Triples) extractions from Dan Connolly's Home Page

A defining characteristic of the Data Web (Context Oriented Web 3.0) is that it facilitates Meshups rather than Mashups.

Quick Definitions:

Mashups - Brute force joining of disparate Web Data

Meshups - Natural joining of disparate Web Data

Reasons for the distinction:

Mashups are Data Model oblivious.

Meshups are Data Model driven.

Examples:

Mashups are based on RSS 2.0 most of the time (RSS 2.0 is at best a Tree Structure that contains untyped or meaning challenged links.

Meshups are RDF based and the data is self describing since the links are typed (posses inherent meaning thereby providing context).

So what? You may be thinking.

For starters, I can quite easily Mesh data from Googlebase (which emits RSS 2.0 or Atom) and other data sources with the Mapping Services from Yahoo!

I can achieve this in minutes without writing a single line of code. I can do it because of the Data Model prowess of RDF (self-describing instance-data), the data interchange and transformation power of XML and XSLT respectively, the inherent power of XML based Web Services (REST or SOAP), and of course, having a Hybrid Server product like Virtuoso at my disposal that delivers a cross platform solution for exploiting all of these standards coherently.

I can share the self-describing describing data source that serves my Meshup. Try reusing the data presented by a Mashup via the same URL that you used to locate Mashup to get my drift.

Demo Links:

1. Googlebase Query URL as an RDF Data Source
2. Perform a simple Data Mesh by adding (via link copy and paste) this Upcoming.org Query Services URL for Ajax Events to the RDF Browsers list of Data Sources (paste into the Data Source URI input field).

What does this all mean?

"Context" is the catalyst of the burgeoning Data Web (Semantic Web Layer - 1). It's the emerging appreciation of "Context" that is driving the growing desire to increment Web versions from 2.0 to 3.0. It also the the very same "Context" that has been a preoccupation of Semantic Web vision since its inception.

The journey towards a more Semantic Web is all inclusive (all "ANDs" and no "ORs" re. participation).

The Semantic Web is self-annotating. Web 2.0 has provided a huge contribution to the self annotation effort: on the Web we now have Data Spaces for Bookmarks (e.g del.icio.us), Image Galleries ( e.g Flickr), Discussion Forums (remember those comments associated with blog posts? ditto the pingbacks and trackbacks?), People Profiles (FOAF, XFN, del.icio.us, and those crumbling walled-gardens around many Social Networks), and more..

A Web without granular access to Data is simply not a Web worth having (think about the menace of click-fraud and spam).

Linking personal posted content across communities: "

With the help of Kingsley, Uldis and I have been looking at how SIOC can be used to link the content that a single person posts to a number of community sites. The picture below shows an example of stuff that I’ve created on Flickr, YouTube, etc. through my various user identities on those sites (these match some SIOC types that we want to add to a separate module). We can also say that each Web 2.0 content item is a user-contributed post, with some attached or embedded content (e.g. a file or maybe just some metadata). This is part of a new discussion on the sioc-dev mailing list, and we’d value your contributions.

Edit: The inner layer is a person (semantically described in FOAF), the next layer is their user accounts (described in FOAF, SIOC) and the outer layer is the posted content - text, files, associated metadata - on community sites (again described using SIOC).

No Tags"

(Via John Breslin - Cloudlands.)

The point that John is making about the Data Web and Interlinked Data Spaces exposed via URIs (e.g Personal URIs), crystallizes a number of very important issues about the Data Web that may remain unclear. I am hoping that by digesting the post excerpt above, in conjunction with the items below, aids the pursuit of clarity and comprehension about the all important Data Web (Semantic Web - Layer 1):

1. Your OpenID can be Your Personal URI (as noted by Henry Story's post about: The Many Uses of OpenID). That that's what I have courtesy of OpenLink Data Spaces (ODS)
2. The above only works unobtrusively (i.e. OpenID and Personal sharing a URI) if Content Negotiation is exploited on the Client and Server sides.
3. TimBL's call out to Share Your Data and Link to Other Data via URIs via post titled: Give Yourself a URI.
4. W3C's Best Practice Recipes for Publishing RDF Vocabularies
5. W3C's Architecture of the World Wide Web - Vol 1 which covers URI Dereferencing (HTTP GET-ing the data that a URI points to)
6. Richard Cyganiak's post titled: Debugging Semantic Web Sites with Curl.

Examples of some of these principles in practice:

1. Chris Bizer, Tobias Gaub, and Richard's Javascript based Semantic Web Client Library
2. DISCO RDF Browser
3. OpenLink Ajax Toolkit's (OAT) RDF Browser
4. OpenLink Interactive SPARQL Query by Example (iSPARQL QBE)
5. Dynamic Data Web Pages from my prior posts [1][2][3]
6. dbpedia (Wikipedia as a Data Web oriented Data Source)
7. And of course this blog post's permalink is a bona fide dereferencable URI.
8. Soren Auer's RDF Browser

And of course there is more to come such as Grandma's Semantic Web Browser which is coming from Zitgist LLC (pronounced: Zeitgeist) a joint venture of OpenLink Software and Frederick Giasson.

Situation Analysis: Pre or Post Oscars, you want to research Forest Whitaker, Helen Mirren, or Jennifer Hudson. What do you do? Go on a screen scrapping and keyword regular expression odyssey? Or you simply lookup a Data Web oriented Data Source like dbpedia.

Here is what I was I was able to knock together using my SPARQL QBE (without writing the SPARQL by hand):

1. Forest Whitaker Data
2. Helen Mirren Data
3. Jennifer Hudson Data.

Note: Just select the "Explore" option when the link-lookup window appears in response to you clicking on any of the links. That said, if you are using the Firefox Linkification extension the page will not work properly (as per this discussion about disabling Linkification) :-(

BTW - I have a comments page, so don't be shy about showing me how you could produce this kind of data driven web page much quicker than I have :-)

Warning: IE6 and Safari (use Webkit instead) cannot process these pages due to the use of Ajax.