Knowledge management is important for theknowledge storage and organization. Otherwiseinformation about new product development can bedispersed or lost, thus, finding efficient manners tostore knowledge in order to be able to search for it andretrieve it is necessary. Ontology is a good solution forthe structuring of information and knowledge andespecially in specific cases as communities of practice.In this paper, we present the followed methodology forthe modeling of the ontology and the technologicalarchitecture of a knowledge management system(KMS), based on this ontology, to facilitate knowledgesharing within special communities. The modelingtechnique is the IDEF0 methodology, the ontology iscodified using the OWL language and the KMS issupported by the OC4J of the J2EE server