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SDTS Revision Project. ANSI INCITS L1 Project to Update SDTS FGDC CWG September 2, 2003. SDTS Revision. Spatial Data Transfer Standard Background/History Philosophy Model Levels Content Implementation. SDTS Revision. Requirements for Change Technology Evolution Standards Evolution
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SDTS Revision Project ANSI INCITS L1 Project to Update SDTS FGDC CWG September 2, 2003 FGDC CWG 09-02-3003
SDTS Revision Spatial Data Transfer Standard • Background/History • Philosophy • Model Levels • Content • Implementation FGDC CWG 09-02-3003
SDTS Revision Requirements for Change • Technology Evolution • Standards Evolution • Role of SDTS • Revision scope • Candidate updates • Plans FGDC CWG 09-02-3003
Background/History • NCDCDS & FICCDC – 1980s • NIST FIPSPUB 173-1 – 1994 • ANSI NCITS 320-1998 • INCITS L1 • InterNational Committee for Information Technology Standards • L1 Geographic Information Systems FGDC CWG 09-02-3003
SDTS Philosophy • Self-documenting • Complete - containing everything needed to enable informed use • Includes metadata (reference system, data dictionary, data quality information, etc.) • Information for software and users to read • Abstract model based Implementation • Modular FGDC CWG 09-02-3003
Model Levels • Conceptual [defns] • The philosophy, ideas, concepts and definitions that form the basis and set the perspective • Logical [modules] • give substantive shape to the ideas from the conceptual layer • Format [files] • Using the structures to build the end product: “a set of files for data transfer” FGDC CWG 09-02-3003
Content What is the content of a transfer? • Features & Spatial Objects • Vector: point, node, chain, polygon, string, arc, link • Raster: grid, pixel • Attributes • user-defined • standard list FGDC CWG 09-02-3003
Content (2) • Metadata • Data dictionary, spatial referencing, data quality, symbology tables, security, global information • Graphics • Ancillary information FGDC CWG 09-02-3003
SDTS Module Categories DATA QUALITY SPATIAL OBJECT GRAPHIC REPRESENTATION GLOBAL • Identification • Catalog • /Directory • /Cross Ref • /Spatial Domain • Security • Coding • Spatial Reference • Internal • External • Registration • Spatial Domain • Data Dictionary • /Definition • /Domain • /Schema • Transfer Statistics Lineage Positional Accuracy Attribute Accuracy Logical Consistency Completeness • Vector: • Point-Node • Line • Arc • Ring • Polygon • Raster: • Raster Definition • Layer Definition • Dimension Definition • Cell • Composite Text Representation Line Representation Symbol Representation Area Fill Representation Color Index Font Index ATTRIBUTE Attribute Primary Attribute Secondary
SDTS Profiles FGDC CWG 09-02-3003
Requirements for Change • Technology Evolution • DCEs, etc. • Standards Evolution • ISO TC 211 standards • OpenGIS Consortiuum specifications • W3C, Etc. FGDC CWG 09-02-3003
Current SDTS Paradigm:Static Data Transfer Data Transfer Decode to target app Encode from source Manifest catalogsschemacoord system... Dataset spatial objectsattributescomposites... FGDC CWG 09-02-3003
Database Server catalogsschemacoord systemgeodata Database Client schemacoord systemrepresentationgeodata Dynamic Interoperability Requests, Features, & Collections Distributed computing environment FGDC CWG 09-02-3003
SDTS Role • SDTS is especially suited for • Blind exchange • Archive • the information content requirements necessitate • self-contained and • self-describing datasets. FGDC CWG 09-02-3003
Setting Revision Scope • Action item to INCITS L1 membership: Review SDTS to identify recent work that has been done that would affect the rewrite of the document, i.e., better/newer concepts, and technologies identified in more recent standards. • Select target constructs to which to map current SDTS constructs. • Select target enhancements (e.g. enhanced semantic modeling). FGDC CWG 09-02-3003
Candidate Mappings • SDTS Constructs map to targets • Abstract (Conceptual) Model • bring into alignment w/ ISO TC 211 19100 suite of standards • Implementation • bring into alignment with ISO TC 211 & OGC specifications • Logical • Encoding FGDC CWG 09-02-3003
Abstract Model Mappings • Conceptual Model ISO 191xx • Feature model • Entity vs Representation 19109 … • Entity Attribute model 19110 (and beyond?) • Spatial Object model • Vector 19107 • Raster 19123 • Graphic representation 19117 FGDC CWG 09-02-3003
Logical Components • SDTS Logical constructs ISO 191xx • Global components • Metadata 19115 • Data Dictionary 19010 (+?) • Spatial Referencing 19111 FGDC CWG 09-02-3003
Implementation - Encodings • Current SDTS encoding: • ISO 8211, Data Descriptive File • Replace ISO 8211 encoding with • XML, specifically GML (Geography Markup Language, OGC and ISO 19136 specification), and • ISO 19115 metadata encodings. • Replace Graphic Symbology with OGC Style Layer Descriptors? FGDC CWG 09-02-3003
Revision Project, Next Steps • Scope the project • Develop work plan • Enlist resources FGDC CWG 09-02-3003
SDTS Revision Contact Robin Fegeas rfegeas@usgs.gov 703-648-4511 FGDC CWG 09-02-3003