Kingsley Idehen's Blog Data Space

Situation Analysis

As the "Linked Data" meme has gained momentum you've more than likely been on the receiving end of dialog with Linked Open Data community members (myself included) that goes something like this:

"Do you have a URI", "Get yourself a URI", "Give me a de-referencable URI" etc..

And each time, you respond with a URL -- which to the best of your Web knowledge is a bona fide URI. But to your utter confusion you are told: Nah! You gave me a Document URI instead of the URI of a real-world thing or object etc..

What's up with that?

Well our everyday use of the Web is an unfortunate conflation of two distinct things, which have Identity: Real World Objects (RWOs) & Address/Location of Documents (Information bearing Resources).

The "Linked Data" meme is about enhancing the Web by unobtrusively reintroducing its core essence: the generic HTTP URI, a vital piece of Web Architecture DNA. Basically, its about so realizing the full capabilities of the Web as a platform for Open Data Identification, Definition, Access, Storage, Representation, Presentation, and Integration.

What is a Real World Object?

People, Places, Music, Books, Cars, Ideas, Emotions etc..

What is a URI?

A Uniform Resource Identifier. A global identifier mechanism for network addressable data items. Its sole function is Name oriented Identification.

URI Generic Syntax

The constituent parts of a URI (from URI Generic Syntax RFC) are depicted below:

What is a URL?

A location oriented HTTP scheme based URI. The HTTP scheme introduces a powerful and inherent duality that delivers:

1. Resource Address/Location Identifier
2. Data Access mechanism for an Information bearing Resource (Document, File etc..)

So far so good!

What is an HTTP based URI?

The kind of URI Linked Data aficionados mean when they use the term: URI.

An HTTP URI is an HTTP scheme based URI. Unlike a URL, this kind of HTTP scheme URI is devoid of any Web Location orientation or specificity. Thus, Its inherent duality provides a more powerful level of abstraction. Hence, you can use this form of URI to assign Names/Identifiers to Real World Objects (RWO). Even better, courtesy of the Identity/Address duality of the HTTP scheme, a single URI can deliver the following:

1. RWO Identfier/Name
2. RWO Metadata document Locator (courtesy of URL aspect)
3. Negotiable Representation of the Located Document (courtesy of HTTP's content negotiation feature).

What is Metadata?

Data about Data. Put differently, data that describes other data in a structured manner.

How Do we Model Metadata?

The predominant model for metadata is the Entity-Attribute-Value + Classes & Relationships model (EAV/CR). A model that's been with us since the inception of modern computing (long before the Web).

What about RDF?

The Resource Description Framework (RDF) is a framework for describing Web addressable resources. In a nutshell, its a framework for adding Metadata bearing Information Resources to the current Web. Its comprised of:

1. Entity-Attribute-Value (aka. Subject-Predictate-Object) plus Classes & Relationships (Data Dictionaries e.g., OWL) metadata model
2. A plethora of instance data representation formats that include: RDFa (when doing so within (X)HTML docs), Turtle, N3, TriX, RDF/XML etc.

What's the Problem Today?

The ubiquitous use of the Web is primarily focused on a Linked Mesh of Information bearing Documents. URLs rather than generic HTTP URIs are the prime mechanism for Web tapestry; basically, we use URLs to conduct Information -- which is inherently subjective -- instead of using HTTP URIs to conduct "Raw Data" -- which is inherently objective.

Note: Information is "data in context", it isn't the same thing as "Raw Data". Thus, if we can link to Information via the Web, why shouldn't we be able to do the same for "Raw Data"?

How Does the Link Data meme solve the problem?

The meme simply provides a set of guidelines (best practices) for producing Web architecture friendly metadata. Meaning: when producing EAV/CR model based metadata, endow Subjects, their Attributes, and Attribute Values (optionally) with HTTP URIs. By doing so, a new level of Link Abstraction on the Web is possible i.e., "Data Item to Data Item" level links (aka hyperdata links). Even better, when you de-reference a RWO hyperdata link you end up with a negotiated representations of its metadata.

Conclusion

Linked Data is ultimately about an HTTP URI for each item in the Data Organization Hierarchy :-)

Related

1. History of how "Resource" became part of URI - historic account by TimBL
2. Linked Data Design Issues Document - TimBL's initial Linked Data Guide
3. Linked Data Rules Simplified - My attempt at simplifying the Linked Data Meme without SPARQL & RDF distraction
4. Linked Data & Identity - another related post
5. The Linked Data Meme's Value Proposition
6. My Del.icio.us hosted Bookmark Data Space for Identity Schemes
7. TimBL's Ted Talk re. "Raw Linked Data".

The original design document (by TimBL) that lead to the WWW (*an important read*) was very clear about the need to create an "information space" that connects heterogeneous data sources. Unfortunately, in trying to create a moniker to distinguish one aspect of the Web (the Linked Document Web) from the part that was overlooked (the Linked Data Web), we ended up with a project code name that's fundamentally a misnomer in the form of: "The Semantic Web".

If we could just take "The Semantic Web" moniker for what it was -- a code name for an aspect of the Web -- and move on, things will get much clearer, fast!

Basically, what is/was the "Semantic Web" should really have been code named: ("You" Oriented Data Access) as a play on: Yoda's appreciation of the FORCE (Fact ORiented Connected Entities) -- the power of inter galactic, interlinked, structured data, fashioned by the World Wide Web courtesy of the HTTP protocol.

As stated in a earlier post, the next phase of the Web is all about the magic of entity "You". The single most important item of reference to every Web user would be the Person Entity ID (URI). Just by remembering your Entity ID, you will have intelligent pathways across, and into, the FORCE that the Linked Data Web delivers. The quality of the pathways and increased density of the FORCE are the keys to high SDQ (tomorrows SEO). Thus, the SDQ of URIs will ultimately be the unit determinant of value to Web Users along the following personal lines:

• Does your platform give me Identity (a URI) with high SDQ?
• Do the Data Source Names (URIs) in your Data Spaces deliver high SDQ?

While most industry commentators continue to ponder and pontificate about what "The Semantic Web" is (unfortunately), the real thing (the "FORCE") is already here, and self-enhancing rapidly.

Assuming we now accept the FORCE is simply an RDF based Linked Data moniker, and that RDF Linked Data is all about the Web as a structured database, we should start to move our attention over to practical exploitation of this burgeoning global database, and in doing so we should not discard knowledge from the past such as the many great examples available gratis from the Relational Database realm. For instance, we should start paying attention to the discovery, development, and deployment of high level tools such as query builders, report writers, and intelligence oriented analytic tools, none of which should -- at first point of interaction -- expose raw RDF or the SPARQL query language. Along similar lines of thinking, we also need development environments and frameworks that are counterparts to Visual Studio, ACCESS, File Maker, and the like.

Related

• Numerati & The Magic of You!

I just stumbled across an post from ITBusines Edge titled: How Semantic Technology Can Help Companies with Integration. While reading the post I encountered the term: Master Data Manager (MDM), and wondered to myself, "what's that?" only to realize it's the very same thing I described as a Data Virtualization or Virtual Database technology (circa. 1998).

Now, if re-labeling can confuse me when applied to a realm I've been intimately involved with for eons (internet time). I don't want to imagine what it does for others who aren't that intimately involved with the important data access and data integration realms.

On the more refreshing side, the article does shed some light on the potency of RDF and OWL when applied to the construction of conceptual views of heterogeneous data sources.

"How do you know that data coming from one place calculates net revenue the same way that data coming from another place does? You’ve got people using the same term for different things and different terms for the same things. How do you reconcile all of that? That’s really what semantic integration is about."

BTW - I discovered this article via another titled: Understanding Integration And How It Can Help with SOA, that covers SOA and Integration matters. Again, in this piece I feel the gradual realization of the virtues that RDF, OWL, and RDF Linked Data bring to bear in the vital realm of data integration across heterogeneous data silos.

Conclusion

A number of events, at the micro and macro economic levels, are forcing attention back to the issue of productive use of existing IT resources. The trouble with the aforementioned quest is that it ultimately unveils the global IT affliction known as: heterogeneous data silos, and the challenges of pain alleviation, that have been ignored forever or approached inadequately as clearly shown by the rapid build up of SOA horror stories in the data integration realm.

Data Integration via conceptualization of heterogenous data sources, that result in concrete conceptual layer data access and management, remains the greatest and most potent application of technologies associated with the "Semantic Web" and/or "Linked Data" monikers.

Related

• InforWorld 2003 Innovator article
• 2006 Podcast Interview with Jon Udell
• Enterprise Information Integration
• One of several posts about our Virtuoso Universal Server and Conceptual Model based data integration
• History of Virtuoso
• Mike Bergman's post titled: WOA: A New Enterprise Partner for Linked Data

After reading Bengee's interview with CrunchBase, I decided to knock up a quick interview remix as part of my usual attempt to add to the developing discourse.

CrunchBase: When we released the CrunchBase API, you were one of the first developers to step up and quickly released a CrunchBase Sponger Cartridge. Can you explain what a CrunchBase Sponger Cartridge is?

Me: A Sponger Cartridge is a data access driver for Web Resources that plugs into our Virtuoso Universal Server (DBMS and Linked Data Web Server combo amongst other things). It uses the internal structure of a resource and/or a web service associated with a resource, to materialize an RDF based Linked Data graph that essentially describes the resource via its properties (Attributes & Relationships).

CrunchBase: And what inspired you to create it?

Me: Bengee built a new space with your data, and we've built a space on the fly from your data which still resides in your domain. Either solution extols the virtues of Linked Data i.e. the ability to explore relationships across data items with high degrees of serendipity (also colloquially known as: following-your-nose pattern in Semantic Web circles).

Bengee posted a notice to the Linking Open Data Community's public mailing list announcing his effort. Bearing in mind the fact that we've been using middleware to mesh the realms of Web 2.0 and the Linked Data Web for a while, it was a no-brainer to knock something up based on the conceptual similarities between Wikicompany and CrunchBase. In a sense, a quadrant of orthogonality is what immediately came to mind re. Wikicompany, CrunchBase, Bengee's RDFization efforts, and ours.

Bengee created an RDF based Linked Data warehouse based on the data exposed by your API, which is exposed via the Semantic CrunchBase data space. In our case we've taken the "RDFization on the fly" approach which produces a transient Linked Data View of the CrunchBase data exposed by your APIs. Our approach is in line with our world view: all resources on the Web are data sources, and the Linked Data Web is about incorporating HTTP into the naming scheme of these data sources so that the conventional URL based hyperlinking mechanism can be used to access a structured description of a resource, which is then transmitted using a range negotiable representation formats. In addition, based on the fact that we house and publish a lot of Linked Data on the Web (e.g. DBpedia, PingTheSemanticWeb, and others), we've also automatically meshed Crunchbase data with related data in DBpedia and Wikicompany data.

CrunchBase: Do you know of any apps that are using CrunchBase Cartridge to enhance their functionality?

Me: Yes, the OpenLink Data Explorer which provides CrunchBase site visitors with the option to explore the Linked Data in the CrunchBase data space. It also allows them to "Mesh" (rather than "Mash") CrunchBase data with other Linked Data sources on the Web without writing a single line of code.

CrunchBase: You have been immersed in the Semantic Web movement for a while now. How did you first get interested in the Semantic Web?

Me: We saw the Semantic Web as a vehicle for standardizing conceptual views of heterogeneous data sources via context lenses (URIs). In 1998 as part of our strategy to expand our business beyond the development and deployment of ODBC, JDBC, and OLE-DB data providers, we decided to build a Virtual Database Engine (see: Virtuoso History), and in doing so we sought a standards based mechanism for the conceptual output of the data virtualization effort. As of the time of the seminal unveiling of the Semantic Web in 1998 we were clear about two things, in relation to the effects of the Web and Internet data management infrastructure inflections: 1) Existing DBMS technology had reached it limits 2) Web Servers would ultimately hit their functional limits. These fundamental realities compelled us to develop Virtuoso with an eye to leveraging the Semantic Web as a vehicle from completing its technical roadmap.

CrunchBase: Can you put into layman’s terms exactly what RDF and SPARQL are and why they are important? Do they only matter for developers or will they extend past developers at some point and be used by website visitors as well?

Me: RDF (Resource Description Framework) is a Graph based Data Model that facilitates resource description using the Subject, Predicate, and Object principle. Associated with the core data model, as part of the overall framework, are a number of markup languages for expressing your descriptions (just as you express presentation markup semantics in HTML or document structure semantics in XML) that include: RDFa (simple extension of HTML markup for embedding descriptions of things in a page), N3 (a human friendly markup for describing resources), RDF/XML (a machine friendly markup for describing resources).

SPARQL is the query language associated with the RDF Data Model, just as SQL is a query language associated with the Relational Database Model. Thus, when you have RDF based structured and linked data on the Web, you can query against Web using SPARQL just as you would against an Oracle/SQL Server/DB2/Informix/Ingres/MySQL/etc.. DBMS using SQL. That's it in a nutshell.

CrunchBase: On your website you wrote that “RDF and SPARQL as productivity boosters in everyday web development”. Can you elaborate on why you believe that to be true?

Me: I think the ability to discern a formal description of anything via its discrete properties is of immense value re. productivity, especially when the capability in question results in a graph of Linked Data that isn't confined to a specific host operating system, database engine, application or service, programming language, or development framework. RDF Linked Data is about infrastructure for the true materialization of the "Information at Your Fingertips" vision of yore. Even though it's taken the emergence of RDF Linked Data to make the aforementioned vision tractable, the comprehension of the vision's intrinsic value have been clear for a very long time. Most organizations and/or individuals are quite familiar with the adage: Knowledge is Power, well there isn't any knowledge without accessible Information, and there isn't any accessible Information without accessible Data. The Web has always be grounded in accessibility to data (albeit via compound container documents called Web Pages).

Bottom line, RDF based Linked Data is about Open Data access by reference using URIs (HTTP based Entity IDs / Data Object IDs / Data Source Names), and as I said earlier, the intrinsic value is pretty obvious bearing in mind the costs associated with integrating disparate and heterogeneous data sources -- across intranets, extranets, and the Internet.

CrunchBase: In his definition of Web 3.0, Nova Spivack proposes that the Semantic Web, or Semantic Web technologies, will be force behind much of the innovation that will occur during Web 3.0. Do you agree with Nova Spivack? What role, if any, do you feel the Semantic Web will play in Web 3.0?

Me: I agree with Nova. But I see Web 3.0 as a phase within the Semantic Web innovation continuum. Web 3.0 exists because Web 2.0 exists. Both of these Web versions express usage and technology focus patterns. Web 2.0 is about the use of Open Source technologies to fashion Web Services that are ultimately used to drive proprietary Software as Service (SaaS) style solutions. Web 3.0 is about the use of "Smart Data Access" to fashion a new generation of Linked Data aware Web Services and solutions that exploit the federated nature of the Web to maximum effect; proprietary branding will simply be conveyed via quality of data (cleanliness, context fidelity, and comprehension of privacy) exposed by URIs.

Here are some examples of the CrunchBase Linked Data Space, as projected via our CruncBase Sponger Cartridge:

1. Amazon.com
2. Microsoft
3. Google
4. Apple

After listening to the latest Semantic Web Gang podcast, I found myself agreeing with some of the points made by Alex Iskold, specifically:

-- Linked Data does not implicitly imply making all your data public

-- Linked Data principles benefit Intranet and Extranet style data integration (trumps alternative distributed database integration approaches any day)

-- Business exploitation of Linked Data on the Web will certainly be driven by the correlation of opportunity costs (which is more than likely what Alex meant by "use cases") associated with the lack of URIs originating from the domain of a given business (Tom Heath: also effectively alluded to this via his BBC and URI land grab anecdotes; same applies Georgi's examples)

-- History is a great tutor, answers to many of today's problems always lie somewhere in plain sight of the past.

Of course, I also believe that Linked Data serves Web Data Integration across the Internet very well too, and the fact that it will be beneficial to businesses in a big way. No individual or organization is an island, I think the Internet and Web have done a good job of demonstrating that thus far :-) We're all data nodes in a Giant Global Graph.

Daniel lewis did shed light on the read-write aspects of the Linked Data Web, which is actually very close to the callout for a Wikipedia for Data. TimBL has been working on this via Tabulator (see Tabulator Editing Screencast), Bengamin Nowack also added similar functionality to ARC, and of course we support the same SPARQL UPDATE into an RDF information resource via the RDF Sink feature of our WebDAV and ODS-Briefcase implementations.

- Produce RDF Linked Data from non RDF Data Sources (Heterogeneous SQL, XML, Web Services)

- Provide highly scalable RDF Data Management via a Quad Store (DBpedia is an example of a live demonstration)

- Sophisticated Deployment of Linked Data that exploits the power of SPARQL

- Powerful WebDAV innovations that simplify read-write mode interaction with Linked Data

- Use Web Data Virtualization to address the pain and frustration associated with Web Data Silos (e.g. OpenLink Data Spaces layer stop Virtuoso that delivers Personal Data Spaces / Unified Storage in the Clouds)

- Deliver a Linked Data development and deployment platform to .NET (VB, C#) , Java, PHP, Ruby, Perl, Python, 'C', C++, and other developers

- More...

For all the one-way feed consumers and aggregators, and readers of the original post, here is a variant equipped hyperlinked phrases as opposed to words. As I stated in the prior post, the post (like most of my posts) was part experiment / dog-fodding of automatic tagging and hyper-linking functionality in OpenLink Data Spaces.

ReadWriteWeb via Alex Iskold's post have delivered another iteration of their "Guide to Semantic Technologies".

If you look at the title of this post (and their article) they seem to be accurately providing a guide to Semantic Technologies, so no qualms there. If on the other hand, this is supposed to he a guide to the "Semantic Web" as prescribed by TimBL then they are completely missing the essence of the whole subject, and demonstrably so I may add, since the entities: "ReadWriteWeb" and "Alex Iskold" are only describable today via the attributes of the documents they publish i.e their respective blogs and hosted blog posts.

Preoccupation with Literal objects as describe above, implies we can only take what "ReadWriteWeb" and "Alex Iskold" say "Literally" (grep, regex, and XPath/Xquery are the only tools for searching deeper in this Literal realm), we have no sense of what makes them tick or where they come from, no history (bar "About Page" blurb), no data connections beyond anchored text (more pointers to opaque data sources) in post and blogrolls. The only connection between this post and them is the my deliberate use of the same literal text in the Title of this post.

TimBL's vision as espoused via the "Semantic Web" vision is about the production, consumption, and sharing of Data Objects via HTTP based Identifiers called URIs/IRIs (Hyperdata Links / Linked Data). It's how we use the Web as a Distributed Database where (as Jim Hendler once stated with immense clarity): I can point to records (entity instances) in your database (aka Data Space) from mine. Which is to say that if we can all point to data entities/objects (not just data entities of type "Document") using these Location, Value, and Structure independent Object Identifiers (courtesy of HTTP) we end up with a much more powerful Web, and one that is closer to the "Federated and Open" nature of the Web.

As I stated in a prior post, if you or your platform of choice aren't producing de-referencable URIs for your data objects, you may be Semantic (this data model predates the Web), but there is no "World Wide Web" in what you are doing.

What are the Benefits of the Semantic Web?

Consumer - "Discovery of relevant things" and be being "Discovered by relevant things" (people, places, events, and other things)

Enterprise - ditto plus the addition of enterprise domain specific things such as market opportunities, product portfolios, human resources, partners, customers, competitors, co-opetitors, acquisition targets, new regulation etc..)

Simple demo:

I am a Kingsley Idehen, a Person who authors this weblog. I also share bookmarks gathered over the years across an array of subjects via my bookmark data space. I also subscribe to a number of RSS/Atom/RDF feeds, which I share via my feeds subscription data space. Of course, all of these data sources have Tags which are collectively exposed via my weblog tag-cloud, feeds subscriptions tag-cloud, and bookmarks tag-cloud data spaces.

As I don't like repeating myself, and I hate wasting my time or the time of others, I simply share my Data Space (a collection of all of my purpose specific data spaces) via the Web so that others (friends, family, employees, partners, customers, project collaborators, competitors, co-opetitors etc.) can can intentionally or serendipitously discover relevant data en route to creating new information (perspectives) that is hopefully exposed others via the Web.

Bottom-line, the Semantic Web is about adding the missing "Open Data Access & Connectivity" feature to the current Document Web (we have to beyond regex, grep, xpath, xquery, full text search, and other literal scrapping approaches). The Linked Data Web of de-referencable data object URIs is the critical foundation layer that makes this feasible.

Remember, It's not about "Applications" it's about Data and actually freeing Data from the "tyranny of Applications". Unfortunately, application inadvertently always create silos (esp. on the Web) since entity data modeling, open data access, and other database technology realm matters, remain of secondary interest to many application developers.

Final comment, RDF facilitates Linked Data on the Web, but all RDF isn't endowed with de-referencable URIs (a major source of confusion and misunderstanding). Thus, you can have RDF Data Source Providers that simply project RDF data silos via Web Services APIs if RDF output emanating from a Web Service doesn't provide out-bound pathways to other data via de-referencable URIs. Of course the same also applies to Widgets that present you with all the things they've discovered without exposing de-referencable URIs for each item.

BTW - my final comments above aren't in anyway incongruent with devising successful business models for the Web. As you may or may not know, OpenLink is not only a major platform provider for the Semantic Web (expressed in our UDA, Virtuoso, OpenLink Data Spaces, and OAT products), we are also actively seeding Semantic Web (tribe: Linked Data of course) startups. For instance, Zitgist, which now has Mike Bergman as it's CEO alongside Frederick Giasson as CTO. Of course, I cannot do Zitgist justice via a footnote in a blog post, so I will expand further in a separate post.

Additional information about this blog post:

1. I didn't spent hours looking for URIs used in my hyperlinks
2. The post is best viewed via an RDF Linked Data aware user agents (OpenLink RDF Browser, Zitgist Data Viewer, DISCO Hyperdata Browser, Tabulator).

ReadWriteWeb via Alex Iskold have delivered another iteration of their "Guide to Semantic Technologies".

If you look at the title of this post (and their article) they seem to be accurately providing a guide to Semantic Technologies, so no qualms there. If on the other hand, this is supposed to he a guide to the "Semantic Web" as prescribed by TimBL then they are completely missing the essence of the whole subject, and demonstrably so I may add, since the entities: "ReadWriteWeb" and "Alex Iskold" are only describable today via the attributes of the documents they publish i.e their respective blogs and hosted blog posts.

Preoccupation with Literal objects as describe above, implies we can only take what "ReadWriteWeb" and "Alex Iskold" say "Literally" (grep, regex, and XPath/Xquery are the only tools for searching deeper in this Literal realm), we have no sense of what makes them tick or where they come from, no history (bar "About Page" blurb), no data connections beyond anchored text (more pointers to opaque data sources) in post and blogrolls. The only connection between this post and them is the my deliberate use of the same literal text in the Title of this post.

TimBL's vision as espoused via the "Semantic Web" vision is about the production, consumption, and sharing of Data Objects via HTTP based Identifiers called URIs/IRIs (Hyperdata Links / Linked Data). It's how we use the Web as a Distributed Database where (as Jim Hendler once stated with immense clarity): I can point to records (entity instances) in your database (aka Data Space) from mine. Which is to say that if we can all point to data entities/objects (not just data entities of type "Document") using these Location, Value, and Structure independent Object Identifiers (courtesy of HTTP) we end up with a much more powerful Web, and one that is closer to the "Federated and Open" nature of the Web.

As I stated in a prior post, if you or your platform of choice aren't producing de-referencable URIs for your data objects, you may be Semantic (this data model predates the Web), but there is no "World Wide Web" in what you are doing.

What are the Benefits of the Semantic Web?

Consumer - "Discovery of relevant things" and be being "Discovered by relevant things" (people, places, events, and other things)

Enterprise - ditto plus the addition of enterprise domain specific things such as market opportunities, product portfolios, human resources, partners, customers, competitors, co-opetitors, acquisition targets, new regulation etc..)

Simple demo:

I am a Kingsley Idehen, a Person who authors this weblog. I also share bookmarks gathered over the years across an array of subjects via my bookmark data space. I also subscribe to a number of RSS/Atom/RDF feeds, which I share via my feeds subscription data space. Of course, all of these data sources have Tags which are collectively exposed via my weblog tag-cloud, feeds subscriptions tag-cloud, and bookmarks tag-cloud data spaces.

As I don't like repeating myself, and I hate wasting my time or the time of others, I simply share my Data Space (a collection of all of my purpose specific data spaces) via the Web so that others (friends, family, employees, partners, customers, project collaborators, competitors, co-opetitors etc.) can can intentionally or serendipitously discover relevant data en route to creating new information (perspectives) that is hopefully exposed others via the Web.

Bottom-line, the Semantic Web is about adding the missing "Open Data Access & Connectivity" feature to the current Document Web (we have to beyond regex, grep, xpath, xquery, full text search, and other literal scrapping approaches). The Linked Data Web of de-referencable data object URIs is the critical foundation layer that makes this feasible.

Remember, It's not about "Applications" it's about Data and actually freeing Data from the "tyranny of Applications". Unfortunately, application inadvertently always create silos (esp. on the Web) since entity data modeling, open data access, and other database technology realm matters, remain of secondary interest to many application developers.

Final comment, RDF facilitates Linked Data on the Web, but all RDF isn't endowed with de-referencable URIs (a major source of confusion and misunderstanding). Thus, you can have RDF Data Source Providers that simply project RDF data silos via Web Services APIs if RDF output emanating from a Web Service doesn't provide out-bound pathways to other data via de-referencable URIs. Of course the same also applies to Widgets that present you with all the things they've discovered without exposing de-referencable URIs for each item.

BTW - my final comments above aren't in anyway incongruent with devising successful business models for the Web. As you may or may not know, OpenLink is not only a major platform provider for the Semantic Web (expressed in our UDA, Virtuoso, OpenLink Data Spaces, and OAT products), we are also actively seeding Semantic Web (tribe: Linked Data of course) startups. For instance, Zitgist, which now has Mike Bergman as it's CEO alongside Frederick Giasson as CTO. Of course, I cannot do Zitgist justice via a footnote in a blog post, so I will expand further in a separate post.

Additional information about this blog post:

1. I didn't spent hours looking for URIs used in my hyperlinks
2. The post is best viewed via an RDF Linked Data aware user agents (OpenLink RDF Browser, Zitgist Data Viewer, DISCO Hyperdata Browser, Tabulator).

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).

I tried to post a comment to Dare Obasanjo's blog post: How Do We Get Rid of Lies on Wikipedia, without success (due to my attempts to add links to the post etc..). Hence a Blog style response instead.

Dare:

I have been through the Wikipedia fires a few times. If you recall that I actually triggered the early Web 2.0 Wikipedia article. along the following lines:

1. Asked one of my staff to start a post with the sole intention of defining Web 2.0 properly
2. I then attempted to edit the initial post
3. I left a typo re. REST
4. Got set on Fire etc... (see very beginning of Wikipedia Web 2.0 history page)

As annoying as the experience above was, I didn't find this inconsistent with the spirit of Wikipedia (i.e. open contribution and discourse). I felt, at the time, that a lot of historical data was being left in place for future reference etc.. In addition, the ultimate aim of creating an evolving Web 2.0 document did commence albeit some distance from "modern man" re. accuracy and meaningfulness as of my last read (today).

Even closer to home, I repeated the process above re. Virtuoso Universal Server. This basically ended up being a live case study on how you handle the Wikipedia NPOV conundurum. Just look at the Virtuoso Universal Server Talk Pages to see how the process evolved (the key was Virtuoso's lineage and it's proximity to the very DBMS platform upon which Wikipedia runs i.e MySQL).

Bearing in mind the size and magnitude of Microsoft, there should be no reason why Microsoft's "Microsoft Digital Caucus" ( legions of Staff, MSDN members, Integrators, and other partners) can't simply go into Wikipedia and participate in the edit and discourse process.

Truth cannot be surpressed! At best, it can only be temporarily delayed :-) Even more so on the Web!