A message conversion system, XML-based metadata semantics description language and metadata repository

Metadata can be used to precisely represent data semantics. It can also serve to improve data sharing and exchange. Because the various types of metadata are created in different ways, they can suffer from a problem of inconsistency. Recently, metadata gateway methods have been researched to solve this problem. However, the performance of the existing approaches based on metadata schemas is poor and their maintenance (adaptation of metadata changes) is time consuming. In this paper, a novel message conversion system is proposed, which functions by separating the heterogeneous mapping information from the mapping rules of the metadata, in order to overcome the drawbacks of the existing metadata gateway methods. The proposed system controls the standardized data elements dynamically based on the Metadata Registry (MDR), which is one of the most important elements of the ISO/IEC 11179 standard. The problems associated with adding supplementary metadata are resolved, since the standard provides for incorporating additional data elements created in the future. MSDL is defined as a protocol which can be used for exchanging messages between heterogeneous systems, and which ensures that all of the systems have their own independent metadata schemas.