Digital Object Identifiers Steve Foreman, C/DRMM WMO;WIS

 What is a DOI?  Options for providing a service  How the WIS catalogue might work Permanent identifiers for data2

What is a DOI? Permanent identifiers for data3

What is a DOI? A digital object identifier (DOI) is a character string (a "digital identifier") used to uniquely identify an object such as an electronic document. Metadata about the object is stored in association with the DOI name and this metadata may include a location, such as a URL, where the object can be found. The DOI for a document remains fixed over the lifetime of the document, whereas its location and other metadata may change. Referring to an online document by its DOI provides more stable linking than simply referring to it by its URL, because if its URL changes, the publisher need only update the metadata for the DOI to link to the new URL. Wikipedia Permanent identifiers for data 4

Options for providing a service Permanent identifiers for data5

DOI services ISO Commercial suppliers ISO Commercial suppliers Data publishers Create metadata with registrar Link metadata to data Use DOI link to cite data Maintain metadata Data publishers Create metadata with registrar Link metadata to data Use DOI link to cite data Maintain metadata Users Enter DOI link into browser to view metadata and possibly access data Users Enter DOI link into browser to view metadata and possibly access data Permanent identifiers for data 6

WIS Discovery Metadata Data publishers Create metadata in WIS Discovery Metadata Catalogue Use WIS unique “FileIdentifier” to cite data Maintain metadata Data publishers Create metadata in WIS Discovery Metadata Catalogue Use WIS unique “FileIdentifier” to cite data Maintain metadata Users Search for “FileIdentifier” in WIS catalogue to find metadata and how to access data. Users Search for “FileIdentifier” in WIS catalogue to find metadata and how to access data. WMO Manual on WIS Permanent identifiers for data 7

Options Permanent identifiers for data 8 WIS Discovery Metadata Programme data should be published in WIS catalogue anyway Work needed to access metadata directly Costs already carried by data providers and GISCs WIS Discovery Metadata Programme data should be published in WIS catalogue anyway Work needed to access metadata directly Costs already carried by data providers and GISCs Purchase DOI service Robust service Assumption that service will be taken over by new provider if current provider fails Explicit cost. Purchase DOI service Robust service Assumption that service will be taken over by new provider if current provider fails Explicit cost.

How the WIS catalogue might work Permanent identifiers for data9

WMO Example urn:x-wmo:md:int.wmo.wis::SZCI01BABJ GTS-bulletin:SZCI01. Tidal elevation observations available from BABJ(PEKING (BEIJING)). ieve&version=1.1&query="urn:x- wmo:md:int.wmo.wis::SZCI01BABJ"&startRecord=1&ma ximumRecords=10&&stylesheet=xsl/dwd-sru.xsl&x-dwd- stylesheetDetailLevel=2 ieve&version=1.1&query="urn:x- wmo:md:int.wmo.wis::SZCI01BABJ"&startRecord=1&ma ximumRecords=10&&stylesheet=xsl/dwd-sru.xsl&x-dwd- stylesheetDetailLevel=2 wmo:md:int.wmo.wis::SZCI01BABJ Permanent identifiers for data 10

Recording provenance of data  WIS Discovery metadata is based on ISO  The WMO standard does not require all elements of the ISO standard to be used, but permits all.  “LI_Lineage” can be used to record how the present dataset was produced  Can include the file identifiers of all data sets used in the creation of the data Permanent identifiers for data 11

Challenges in sing the WIS catalogue Permanent identifiers for data 12 Set up the shortened URL mechanism Require GAW data to provide LI_Lineage in their datasets in a standard way Set up the shortened URL mechanism Require GAW data to provide LI_Lineage in their datasets in a standard way Format the search look-up responses for humans, and include more information in them. Make the search more “intelligent” so that can distinguish between “FileIdentifiers” labelling a record, and those in the LI_Lineage Format the search look-up responses for humans, and include more information in them. Make the search more “intelligent” so that can distinguish between “FileIdentifiers” labelling a record, and those in the LI_Lineage

Thank you for your attention Permanent identifiers for data13