Ontology-based techniques for data distribution and consistency management in a SWIM environment

Effective use of the Semantic Container approach developed in BEST depends on the existence of a Semantic Container Management system controlling the replication, distribution and consistency of containers. The deliverable provides a metamodel describing the information needed to implement such a Semantic Container Management System. In the field of distributed databases, there are many existing techniques for distribution, replication and consistency management, mostly based on a single generic data model. In BEST we refine this, using different types of models for different kinds of information. High availability of information and low network load are key goals for the success of the SWIM approach. Semantic containers, supported by a Semantic Container Management System, can contribute significantly to these goals. The metamodel distinguishes between logical and physical containers, and indicates which containers are allocated to which nodes. It also allows definition of versions of containers, supporting consistency management and different forms of synchronization. Finally, the metamodel allows for traceability of data provenance, and definition of composite containers that gather data from lower-level elementary containers. We illustrate the proposed metamodel using NOTAMs as example. We stress, however, that the semantic container approach applies to other types of ATM information as well. The deliverable also outlines the architecture of a Semantic Container Management system, describing the distribution of the metadata and software components needed to implement it.