The paper is related to specialized software advanced applications. Today, the emergence of distributed systems was supported by the development of computer networks and Internet. This development has supported the opening of systems and distribution of components. If there are protocols and standards for access, distribution, shared objects and data base, that is unfortunately not the case for spatial data base. These spatial data which were formerly ignored in the information systems of companies and organizations are now taken into account and are stored in the same way as textual data. Unfortunately, their dynamic distribution and access encounters a serious lack of device and tools which can facilitate this distribution. The paper proposes a canonical language for handling and distribution of spatial data which is based on metadata registered in a federation of electronic directories distributed on the Web.