OSGeodata: Unterschied zwischen den Versionen

Version vom 3. August 2006, 20:38 Uhr

Experimental pages for OSGeodata Mailing List on OSGeo.org.

Goal

Citation from Jo Walsh: "Managing metadata well is the key to making a repository of open geographic data really useful and re-usable. Creating metadata can be a dull chore. Part of the problem is over-focus on production, rather than consumption; on standards, rather than on usage. The Geodata Committee at OSGeo has been working on a "simplest useful thing" approach to geographic metadata...".

Comparison between WFS and OAI-PMH

WFS:

• WFS is short for 'Web Feature Service'
• Background: A de-facto standard in GIS world owned by OGC
• Requests: GetCapabilities, DescribeFeatureType, GetFeature, Transaction, LockFeature
• Query:
  • Standard query includes spatial constraints (but no temporal?)
  • Needs to be profiled
• Availability and outreach of services, tools and (open source) software:
  • Open source software see freegis.org
• ...

OAI-PMH:

• OAI is short for 'Open Archives Initiative', PMH is short for 'Protocol for Metadata Harvesting'.
• Background: Was initiated by libraries, universities, museums and galleries to 'open access' (OA) free online availability of digital content.
• Requests: Identify, ListMetadataFormats, ListSets, ListIdentifiers, ListRecords, GetRecord.
• Query:
  • Standard query includes temporal constraints (but no spatial).
  • Needs to be extended
• Availability and outreach of services, tools and (open source) software:
  • Open source software see OAI-PMH tools
  • Gateways available from publishing files to others
  • Google reads it as a Sitemaps file (how to submit) and Internet Archive uses it among others.
• ...

Common:

• RESTful
• Both can be profiled to respond an 'output content model' which has yet to be defined.

Weblinks

• OGC's CSW 2.0
• OGC's WFS
• OAI-PMH - Open Archives Initiative Protocol for Metadata Harvesting 2.0