On-To-Knowledge - Content-driven Knowledge-Management through Evolving Ontologies.

On-To-Knowledge is an RTD project funded by the European Comission, IST-1999-10132. The project develops methods and tools and employ the full power of the ontological approach to facilitate knowledge management. The On-To-Knowledge tools will help knowledge workers who are not IT specialists to access company-wide information repositories in an effcient, natural and intuitive way. OntoText joined the On-To-Knowledge project November 2001 in order to develop ontology middleware and reasoning modules. This role is shortly presented below. More information can be found in "Ontology Middleware: Analysis and Design" document.

The middleware can be seen as "administrative" software infrastructure that makes the results of the On-To-Knowledge project easier for integration in real-world applications. The central issue is to make the methodology and modules available to the society in a shape that allows easier development, management, maintenance, and use of middle-size and big knowledge bases. In the light of these objectives the following core features are targeted:

• Versioning (tracking changes) of knowledge bases;
• Access control (security) system;
• Meta-information for knowledge bases.

KCS provides the knowledge engineers with the same level of control and manageability of the knowledge in the process of its development and maintenance as the source control systems (such as CVS) provide for the software. However, KCS is not only limited to support the knowledge engineers or developers - from the perspective of the end-user applications, KCS can be seen as equivalent to the database security, change tracking (often called cataloguing) and auditing systems. KCS is carefully designed so to support these two distinct use cases.

From a more general perspective, an ontology middleware system should serve as a flexible and extendable platform for knowledge management solutions. Thus, it has to provide infrastructure with the following features:

• A repository providing the basic storage services in a scalable and reliable fashion. This role is already fulfilled by SESAME.
• Knowledge control - the KCS introduced above.
• Multi-protocol client access to allow different users and applications to use the system via the most efficient "transportation" media. There is already some level of support for it in the SESAME architecture - it will be extended to meet the requirements of a true ontology back-end.
• Support for plugable reasoning modules suitable for various domains and applications. This ensures that within a single enterprise or computing environment one and the same system may be used for various purposes (that require different reasoning services) so providing easy integration, interoperability between applications, knowledge maintenance and reuse.

An example for plugable reasoning service is BOR - a reasoner that complies with the DAML+OIL model-theoretical semantics. Most of the classic reasoning tasks for the description logics are available, including realisation and retrieval. Few innovative services, such as model checking and minimal ontology extraction, are also implemented. The full set of functional interfaces allows a high level of management and querying of DAML+OIL ontologies, represented in Sesame repository. Read more at http://www.ontotext.com/bor/