One of the key features that the semantic web brings us is unique identifiers for a global distributed database. User-oriented tools for the semantic web are largely one-off applications with development and support coming from programmers with considerable investment in the learning curve. But what are the alternatives? What semi-coddling environment can be presented to a user for simpler application development? For deployment and market experience, we can look to Lotus Notes and several similar open-source development efforts.
In Lotus Notes, a relatively inexperienced developer may craft applications for a user base with little computer saavy. This was a goal of Notes and it has proven itself in many large corporate environments. Like most 4GLs, it has a legacy of macro functions with "controversial" side-effects but the underlying relationship (@@@ name) identification and data and structure replication has provided a solid environment for large distributed databases.
What if such an engine were built on top of the semantic web?
Getting data into the semantic web is pretty easy; one publishs it in RDF, N3, SOAP, or perhaps colloquial XML with namespaces. One could argue that publishing any data in a domain that has a defined mapping to semantic web structures constitutes publishing it in the semantic web as consumers may get to that data via a gateway. The problem wiht this model is that great effort needs to go into harvesting this data. Search engines or domain-specific data aggregators like user agents need to maintain large lists of data sources. Source maintanance may be semi-centralized through inderection but this still represents considerable administrative effort.
There are ususally four compelling arguments for aggregating data into a centralized relational database.
Some organizations choose to go all out on data centralization, either through all-encompassing relational databases, or through more fluid databases like Notes.
All of the above arguments except for structural clarity are valid for promoting larger centralized semantic web databases. That data is available in, say, RDF, does not make it easier or faster to access, or easier to maintain. The structure inherent to the semantic web will make the process of data centralization simpler and therefor probably even more attractive than the aggregation of chaotic data into a relational database.
There are some reasons not to take centralization too far.
Eric Prud'hommeaux Last modified: Mon Apr 2 08:42:57 EDT 2001