Achieving Network Enabled Capabilities through the Definition, Understanding and Dissemination of Metadata

1
Achieving Network Enabled Capabilities through
the Definition, Understanding and Dissemination
of Metadata
London26-27 January 2005

• Olaf ØstensenChairman of ISO/TC 211 Geographic
  information/GeomaticsNorwegian Mapping and
  Cadastre Authority

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The fundament of geospatial technology in the
networked age

• INTEROPERABILITY
• and metadata is necessary to achieve
  interoperability
• semantic interoperability (understanding the
  information)
• technical interoperability (e.g. enabling
  interfaces to communicate)

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What is metadata ?

• Data about Data
• provides information about the identification,
  the extent, the quality, the spatial and temporal
  schema, spatial reference, and distribution of
  digital geographic data
• Ensures the right data for the right purpose
• Ensures that information is used correctly

Geospatial data has a long history using Metadata
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Paper Maps
Identification
Symbols
Date
Sources
Producer
Title
Reference system
Navigation notices
Scale
Accuracy
Location
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Aerial Photos
Date
Location
Originator
Altitude
Obliqueness
Identifiers
Time
Focal length
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Map catalogs
Format
Location
Size
Scale
Series name
Area coverage
Characteristics
Distribution information
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Digital data packaging
Identifier
Date
Format
Location
Originator
Contact information
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If we do not know the metadata

• how can we know the currency?
• how can we know the accuracy?
• how can we know the completeness?
• .
• .
• HOW CAN WE TRUST THE INFORMATION?

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Up to now

• we have known the producer
• we have known the data series
• we had an overall view of currency, quality and
  completeness
• with the networked services, all this is changing
  

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In the networked age

• a vast amount of data that can be downloaded
• more important, an enormous amount of geospatial
  services that we can connect to
• METADATA AND METADATA UNDERSTANDING BECOMES
  MANDATORY!

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Metadata is necessary
!
Metadata - datasets
Metadata - services
a variety of content,reference and thematicdata
a rich set of functionality- services
a variety of appli-cations

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User Environment

• Understand the Model
• How features are represented
• Connectivity
• Understand the Content
• Why features are included or excluded
• Understand the Point-of-View
• Business/Commercial
• Environmental/Scientific
• Military/Defense/Intel

Pleasantville
Pleasantville
Pleasantville
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Processing Environment

• Support user Decisions
• Identify multiple datasets within an application
• Know the good and bad areas
• Merging data (which is the better data?)
• Currentness
• Quality
• Support Computer Processing
• Application software functions
• Capabilities, access
• Guide software through the data

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Metadata - Supporting Geographic Dataand
Services Life Cycle
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Metadata perspectives

• Why is metadata more important now?
• Expansion in the use of Geographic Information
• Proliferation of data
• Non-geographers using geospatial data
• The producer is not the user
• Geospatial data is imperfect
• A model, a point of view
• Assumptions, limitations, approximations,
  simplifications
• Geospatial data is expensive
• Reuse
• Data management
• Why should it be standardized?
• Provide an understanding of data around the
  Globe and across information communities

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ISO 191152003
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ISO - the International Organization for
Standardization

• a NGO based in Geneva
• established in 1947
• the authorized publisher of global standards
• published more than 14 000 standards (e.g. ISO
  9000- and ISO 14000-series)
• based upon national membership 148 countries
  participate

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ISO 191152003Scope

• ...the schema required for describing geographic
  information and services
• ...information about the identification, the
  extent, the quality, the spatial and temporal
  schema, spatial reference, and distribution of
  digital geographic data
• ...applicable to the cataloguing of datasets,
  clearinghouse activities, and the full
  description of datasets for a wide range of
  geographic applications
• applicable to geographic datasets, dataset
  series, and individual geographic features and
  attributes
• ...may be used for other forms of geographic data
  such as map, charts, textual documents

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ISO 191152003

• Designed
• to support geographic information
• to work with wider information technology
  standards and practices
• to serve the global community, in a
  multi-national, multi-language environment
• based on a foundation of national, regional, and
  special information community standards and
  experiences
• Developed through a rigorous, consensus ISO
  process
• Provides a foundation for national, regional, and
  global interoperability

Semantic Interoperability
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ISO 191152003 Metadata applications
FeatureType
DataSet
0..
0..
0..
1..
Metadata
Feature
0..
1..
1..
0..
PropertyType
0..
0..
0..
Aggregate DataSet
FeatureAttribute
0..
OtherAssociation
Initiative
Series
StereoMate
Platform
Sensor
ProductionSeries
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Recommended core metadata for geographic datasets

• Dataset title
• Dataset reference date
• Dataset responsible party
• Geographic location of the dataset (by four
  coordinates or by geographic identifiers)
• Dataset language
• Dataset character set
• Dataset topic category
• Spatial Resolution
• Abstract describing the dataset
• Distribution format

• Additional extent information (vertical and
  temporal)
• Spatial representation type
• Reference system
• Lineage statement
• On-line resource
• Metadata file identifier
• Metadata standard name
• Metadata standard version
• Metadata language
• Metadata character set
• Metadata point of contact
• Metadata time stamp

• Mandatory

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Other metadata standards under work

• ISO/TS 19139 Geographic Information Metadata
  XML Schema Specification
• ISO 19115-2 Geographic Information Metadata
  Part 2 Extensions for Imagery and Gridded Data

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ISO 19115-2 Geographic Information Metadata
Part 2 Extensions for Imagery and Gridded Data

• Scope
• This International Standard extends ISO
  191152003 Geographic Information Metadata by
  defining the schema and additional metadata
  required for imagery and gridded data

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ISO 19139Geographic Information Metadata
XML Schema Implementation

• Defines spatial metadata XML (smXML) encoding
• an XML Schema implementation derived from ISO
  19115-Geographic information Metadata
• XML Schema
• More rigorous validation of compliance
• More exact representation of UML
• Based on Comprehensive Profile ISO 19115
• Separate from ISO 19115
• More easily evolve with changes in technology
• Quickly establish implementation of ISO 19115

Technical Interoperability
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Liaison Organizations and Related Work
Commercial SPOT
National participation
Consortium IEEE ISPRS WMO
ISO 19115 - 2 Imagery Extensions
FGDC/NASA Metadata Remote Sensing Extensions
ISO 191152003
IHO S-57 Edition 4
SMPTE
JTC1/SC24 ISO/IEC 12087-5 BIIF
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Metadata Portals

• Portal gateway, place of entry
• Producers
• Advertise, expose products
• Share information about holdings
• Provide an understanding of data and services
• Users
• Perform efficient searches by requirements
• Discover data and services
• Determine fitness for use
• Acquire access information

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What are users looking for?

• Data for use in GIS software
• GIS Services - mapping, geoprocessing
• Geospatial applications
• Planned data acquisitions
• Events, activities and information

A metadata portal contains metadata for all of
the above
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Metadata and INSPIRE Directive (proposal)
Article 7 Member States shall establish and
operate infrastructures for spatial information
in accordance with this Directive. Chapter
II Metadata Article 8 1. Member States shall
ensure that metadata are created for spatial data
sets and services, and that those metadata are
kept up to date. 2. Metadata shall include
information on the following 3. Member States
shall take the necessary measures to ensure that
metadata are complete and of high quality.
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Metadata and INSPIRE Directive (proposal)
Article 18 1. Member States shall establish and
operate a network of the following services for
the spatial data sets and services for which
metadata have been created in accordance with
this Directive (a) discovery services making it
possible to search for spatial data sets and
spatial data services on the basis of the content
of the corresponding metadata and to display the
content of the metadata (b) view services making
it possible, as a minimum, to display, navigate,
zoom in/out, pan, or overlay spatial data sets
and to display legend information and any
relevant content of metadata (c) download
services, enabling copies of complete spatial
data sets, or of parts of such sets, to be
downloaded (d) transformation services, enabling
spatial data sets to be transformed (e) invoke
spatial data services services, enabling data
services to be invoked. Those services shall be
easy to use and accessible via the Internet or
any other appropriate means of telecommunication
available to the public.
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Geospatial Portal Architecture
OGC Catalog Services (Z39.50 CS-W)
OGC WMS, WFS, WCS Mif, Shp . . .
OAI Protocol for Metadata Harvesting
ISO 19115 Metadata/ ISO 19139 Metadata Implementat
ion Specification
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What is a metadata portal?
Search Navigation
View
Spatial
Users
Categories
Thesaurus
Supporting Data Sets
Metadata
Publishers
Partners
Service broker
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Exposing Metadata
Discover
Author
Publish
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Searching for Geospatial Data
Portal browser
Metadata Explorer
Metadata Catalog
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Searching MetadataThrough a Portal
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SummaryISO Metadata

• Many flavors of interoperability
• Metadata a key factor enabling interoperability
• Essential for all aspects of spatial data
  handling
• Locate
• Evaluate
• Extract
• Employ
• Metadata in the ISO 19115 standard
• Semantic interoperability
• Provides a common understanding
• Expanded networks
• Global Interoperability

• ISO TC 211 is taking the next steps
• Expanding for imagery
• Implementation specification
• Technical interoperability
• Metadata Portals
• Fast, direct access
• Increased easy participation
• Key lifecycle component
• Standards based tools make it easy

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Summary

• metadata supports assessment of information on
  the internet
• metadata is necessary for connecting to network
  services (e.g. wms, wfs, wcs, )
• metadata is a necessary although not sufficient
  condition to trust information in the networked
  environment!

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Thank you !

• also thanks to David Danko, project leader in
  metadata in ISO/TC 211 for providing input to
  this presentation