1/19 Oct 05 Standardization unit DT.TN/ Content Management using the ISO/TC 211 standards ESDI Workshop on CSL and Tools (on behalf of IGN France, DGIWG and Eurogeographics) Modèle TN –1.0 Through experiences Translation of GI Data PT MGCP

2/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data Context French NMA (IGN), early to mid 90’s –The base principles are still applicable!!! Member of the IGN exchange format team –Specification of (generic) translator between: GIS (Arc Info, Tigris, Geoconcept…) or external exchange format (EDIGéO, DXF, …) the IGN internal exchange format for vector data –Configuration of the translators for different data product Content Management Translation of GI Data PT MGCP

3/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data Generic translators Translation rules based at a high conceptual level –General Feature Model for the semantic aspects –Metadata/Quality schema –Geometry/Topology schema Use of configuration files for a given data product Content Management Translation of GI Data PT MGCP

4/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data Need for transformation tools Generic transformation tools to manage the major conceptual mismatches –« application schema » transformation –Geometry/Topology transformation –CRS transformation Sometimes, need for pre/post processing using the GIS abilities Content Management Translation of GI Data PT MGCP

5/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data “exchange convention” An agreement between a data provider and a data customer on a full interchange process –pre processing –translator configuration –transformation tools and their configuration –controls –post processing A principle to keep in mind for any kind of interchange –What about a “delivery specification” standard? Content Management Translation of GI Data PT MGCP

6/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data The technological gaps - GFM No more geometry-oriented feature types –multiple geometry –separation of geometry and topology –different management of topology no or less layering constraints Object-oriented approach –Inheritance/abstraction –Operation!? Formalisation of constraints Content Management Translation of GI Data PT MGCP

7/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data Technological opportunities Well formalised and standardised GI concepts –modular abstract schemas (ISO 19115, ISO 19107, ISO 19108, …) Should ease the establishment of transformation rules (Divide to conquer) –a standardised GFM a reference for establishing transformation rules –disconnection of the concepts and their encoding Distributed environment –Emergence of Web Services CRS transformation, data access and transformation A Web service is a standard interface for transformation tools Content Management Translation of GI Data PT MGCP

8/19 Oct 05 Standardization unit DT.TN/ Experience in translation and interchange of GI data Some technological opportunities, but … Technological gaps to be managed –the GI system / software are not yet fully ready to support the ISO/TC 211 standards (GFM and abstract schemas) –Need to move forward in a controlled manner simple features, enhanced simple features, … implies a high level (OGC, ISO/TC 211, …) scheduling No miracle –The processing requirements are still the same Web Services will not necessarily met all those processing requirements but, we can take advantage of our experience –“High level transformation rules” still needed (at least as long as systems/softwares don’t handle the GFM) –Dangerous to rely the GI Technology on the XML Technique Need for formalising some of the OGC Specification in a CSL (UML?) e.g., FE, WFS-X A consistent use of the ISO standards is a challenge Content Management Translation of GI Data PT MGCP

9/19 Oct 05 Standardization unit DT.TN/ ISO Experience About defining encoding rules It’s a hard task because –it involves mapping at a high conceptual level and so, a good understanding of CSL and XML concepts –it requires to consider the actual or short/mid term usage of the encoding (and CSL) It’s consequently an area for standardisation –with possible difficulties to come up to an agreement –with a need for clear requirements It’s possible –but, it requires the involvement of relevant experts –the higher is the representation of the domain actors, the better is the result Content Management Translation of GI Data PT MGCP

10/19 Oct 05 Standardization unit DT.TN/ ISO Experience Encoding rules and transformation tools Transformation tools are needed, but are accessory –Two pieces of software have been developed by ISO PT members and have produces compatible result A clear understanding of the encoding rules is the challenge The issue is a general standardisation issue –Generation of XML Schemas is not achieved so often Encoding rules make the transformation tool easier to develop The encoding rules and transformation tools are not dependant on the CSL Tool –the effective transformation can be processed outside of CSL Tool, using or not a “standard CSL exchange format” Standardisation of XMI is a challenge in term of CSL Tool use, but is not a specific issue for transformation tools Content Management Translation of GI Data PT MGCP

11/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience Context A Military Co-production initiative for 1:50K equivalent scale vector database Product content varies depending on the sources available –will to keep track of the content variation –General and common content requirements, –but, the content reqs may be specialised Use of the DFDD data dictionary (FACC) as the reference for GI concept definitions Data interchange by transfer: –ESRI SHAPE format used for the data, but GML may be used later Content Management Translation of GI Data PT MGCP

12/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience Application schema vs Feature catalogue (1/2) What are the respective roles of application schema and feature catalogue? Content Management Translation of GI Data PT MGCP

13/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience Application schema vs Feature catalogue (2/2) Application schema –Expressed using a CSL –Managed using a CSL Tool => Can’t be easily queried –Provide a useful visual understanding of a product content –Depending on CSL, allow for user community extensions (tagged information) Feature Catalogue –Abstract specification which can be implemented as a database or register and as an interchange format (e.g. XML) –Can be more easily queried, but is is not designed for display –Is considered limited to the semantic aspect of a product content (no geometry/topology, no metadata/quality, …) –Provide a mean to rely the Feature types, Attributes Types, Association types and roles to external concepts e.g. a normal dictionary, a data dictionary or a more “abstract” FC Content Management Translation of GI Data PT MGCP

14/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience MGCP assumption Limiting the use of ISO (FC) to the semantic aspects is like using UML for abstract classes!? –ISO abstract schemas can support any types of attributes, including metadata, geometry, topology, … –It is possible to establish abstract FC dealing only with the semantic aspect of data products –But, it is also possible to establish concrete FC handling the full data product content and referencing an abstract FC FC can be used for managing product contents –An application schema can be derived from a concrete FC –the product content can be accessed, queried, modified and interchanged more conveniently Content Management Translation of GI Data PT MGCP

15/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience Implementation of ISO XSD XSD Encoding rules ISO Amndt MGCP XSD MGCP Profile General FC Raw XML Export Excel Macro FC MGCP XML XSL Transf. Is compliant with XSL view DFDD References Specialised FC References Profiled FC MGCP XML Raw XML Export Content Management Translation of GI Data PT MGCP

16/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience From the MGCP FC to an AS Generation of a UML AS from the XML FC –1 hour to have an XSL generating a cat file –A very poor AS generated as expected no Association, no inheritance, … the initial FC was non as poor Ad hoc meeting for establishing rules for enhancing the application schema –use of DFDD codes as stereotypes –rules for classification (inheritance) –rules for expressing topological constraints Optimisation of the AS –FC can be viewed as expressing a profile of the new AS –An abstract FC could be generated from the new AS Content Management Translation of GI Data PT MGCP

17/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience Issues Generation of control tools from CSL constraints –Dream or reality? –Literal conformance requirements to be documented Compatibility of AS related to a single abstract FC Content Management Translation of GI Data PT MGCP

18/19 Oct 05 Standardization unit DT.TN/ The MGCP Experience The GI standardisation paradox Data product specification Data Dictionary Feature Catalogue Application Schema GML Schema Standardisation Time axis Yesterday - ISO/DIS GML GML 2.x Later- ISO/DIS Today- This workshop Tomorrow - ISO but, experimental use When? NWIP Content Management Translation of GI Data PT MGCP

19/19 Oct 05 Standardization unit DT.TN/ Conclusion Content Management Translation of GI Data PT MGCP No need for Geo-specific UML softwares –but, use/enhance ISO/TC 211 profile of UML Let’s use the available standard to manage the data product content independently of any CSL –ISO 19110, ISO –Contribute to ISO Need for new standards –delivery specification –AS/FC transformation