Recently I developer a web service for the semantic web called PingtheSemanticWeb. The goal of this service is to be notified that a new semantic web document has been published on the Web; to archive its location; and to give its location to other web services: it is called a pinging system, a sort of hub for semantic web documents.
Many people think that the semantic web is only accessible and useful for researcher. They were probably right five years ago; but now I see the landscape of the Web changing.
More and more web services related to the semantic web are emerging. More and more of these services are starting to interact together. More and more people are using the semantic web technologies and services in their day to day work.
This blog post is about an emerging architecture of semantic web services.
The Semantic Radar for FireFox
The characteristic of semantic web documents is that they are not intended for humans, but for software agents (like search engines crawlers, personal agent software like Web Feed Readers, etc). The consequence is that humans do not see these documents, so no body really knows that the Semantic Web is growing and growing on the current Web.
This is the purpose of this new Semantic Radar: unveiling the Semantic Web to humans.
The Semantic Radar: much more than that
This plug-in is much more than that. Effectively, each time it detects one of these semantic web documents, it will notify PingtheSemanticWeb.com web service.
This is where the interaction between semantic web services and applications are starting to emerge. Now Web browsers will detect semantic web documents and notify a web service acting as a central repository for semantic web documents.
The New Semantic Web Services Environment
A couple of years ago, everything was looking good on paper; now everything is starting to look good on the Web.
Bellow is a simple schema describing the interaction between some technologies and web services of the Semantic Web.
This is not the semantic web, but this is a small portion of it; this is an example of how it is all working together: this is a sort of Semantic Web Mashup.
Semantic Web Documents (RDF)
This is what the semantic web is: a sea of documents formatted in such a way that they explicit the semantic of their content.
- RDF. The more widespread type of semantic web documents.
- FOAF. Documents describing the person.
- SIOC. Documents describing online communities.
- DOAP. Documents describing a project.
All these documents are generated (created) by special application called exporters. An exporter is a program that will generate a semantic web document with a source of data (normally a database).
Some of these exporters will be able to ping (sending a notification) to PingtheSemanticWeb.com pinging service when they generate or update a new semantic web document (like Talk Digger and ODS, or blogs using WordPress, b2Evolution or DotClear that added PinttheSemanticWeb.com to their servers to ping when they publish new articles on their blog).
This is a sub-class of exporters. They are community web sites with thousands of users that are exporting some of their content using semantic web documents.
- Talk Digger. This web application is exporting the profile of its users as FOAF documents and exports its conversations (because it is a web service that search for conversations on the Web) as SIOC documents.
- LiveJournal. This is a blogging community web site with 10 million of registered users that export its user profiles as FOAF documents.
- ODS. This is a set of Web2.0 applications like blogs, Wikis, forums, etc. It exports all its data using documents like FOAF, SIOC, DOAP, and other RDF ontologies.
This is another sub-class of exporters. They are generally plug-ins that individual users add to their software to let them export their data in one of these type of documents.
One good example of such exporters is plug-ins for blogging softwares:
- WordPress SIOC exporter. It let the WordPress blogging software export its data in SIOC document.
- b2Evolution SIOC exporter. It let the b2Evolution blogging software export its data in SIOC document.
- DotClear SIOC exporter. It let the DotClear blogging software export its data in SIOC document.
Even if many exporters will automatically ping PingtheSemanticWeb.com service, not all of them will (by example, LiveJournal is not). Also, individual people will create and publish semantic web documents without pinging the system too.
In such a case, the document could be “invisible” to the “semantic web” because nobody knows they exist.
This is the reason why you have another kind of tool that let people ping specific web pages. That way, they have the power to say: Hey! I found that semantic web document; you can find it there.
- Semantic Radar for FireFox. This tool will notify the pinging server if the user encounters a semantic web document while he is surfing the Web.
- Bookmarklet. This is the PingtheSemanticWeb.com bookmarklet that let a user click on a bookmark to notify the service that a semantic web document is present on the page is he currently looking at.
- Website. This is the web interface of the service that let people enter URL of document they found to include them to the service.
Ping the Semantic Web.com
This semantic web service is at the center of the architecture I present today. It will act as a multiplexer for semantic web documents location. It will receive the location of semantic web document from a multitude of sources; it will archive them; and it will re-distribute the location to other web services or software agents.
This is the place where the semantic web is truly unveiled; and this is the place where people will go to know where semantic web documents live.
Other web services and software agents
Other application like Swoogle has to crawls the Web to find Semantic Web documents. This is why Swoogle will integrate PingtheSemanticWeb in their infrastructure: they will directly have access to a full list of RDF documents ready to be included in their search engine.
Other web services like the SIOC explorer will import only the list of new SIOC documents.
So for all web services or software applications there is a place where they can find a list of new semantic web document ready to be used.
What I think is that the synergy created by this architecture could propel the adoption of the Semantic Web.
More people will create semantic web documents if more web services are using them.
Web services will use more semantic web documents if more people will create them.
More web services will create semantic web documents if more people will use them.
More people will use semantic web documents if more web services create them.
In a case or another, this interaction will be driven by:
How many semantic web documents are accessible (quickly and easily)
The answer to this need is PingtheSemanticWeb service; pinging tools like the Semantic Radar; and a set of dedicated users that find and ping “semantic web documents”.