DIF Recommendations

From Federation of Earth Science Information Partners

SPACE HOLDER FOR DESCRIPTION

DIF for Data Discovery - Required

The Directory Interchange Format (DIF) is a NASA metadata format used to create directory entries that describe scientific data sets. The attributes in the spiral below are required by the DIF standard. Additonal documentation is available via the following online references:

Source: Interactive Write a DIF Guide DIF standard specification

ConceptDescriptionDialect (Fit) Paths
Metadata IdentifierA phrase or string which uniquely identifies the metadata file/record.DIF /dif:DIF/dif:Entry_Id
ISO /*/gmd:fileIdentifier/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:metadataIdentifier/mcc:MD_Identifier
Resource TitleA short description of the resource. The title should be descriptive enough so that when a user is presented with a list of titles the general content of the data set can be determined.DIF /dif:DIF/dif:Entry_Title
DIF /dif:DIF/dif:Data_Set_Citation/dif:Dataset_Title
ECHO /*/echo:ShortName>/*/echo:LongName
ECS /*/ecs:ShortName > /*/ecs:LongName
DCAT dct:title
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:citation/fgdc:citeinfo/fgdc:title
ISO /*/gmd:identificationInfo/*/gmd:citation/gmd:CI_Citation/gmd:title/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:citation/cit:CI_Citation/cit:title/gco:CharacterString
KeywordA word or phrase that describes some aspect of a resource. Can be one of several types.

Note: The general identification keywords usually have a type of "theme" and are refered to as "theme keywords". Other types and vocabularies are used for other information. Service Entry Resource Format (SERF) requires a Science and a Service GCMD Keyword. This concept is called "Subject" in the CSW Specification.
DIF (1) /dif:DIF/dif:Parameters/dif:Category
DIF (1) /dif:DIF/dif:Parameters/dif:Topic
DIF (1) /dif:DIF/dif:Parameters/dif:Term
DIF (1) /dif:DIF/dif:Parameters/dif:Variable_Level_1
DIF (1) /dif:DIF/dif:Parameters/dif:Variable_Level_2
DIF (1) /dif:DIF/dif:Parameters/dif:Variable_Level_3
DIF (1) /dif:DIF/dif:Parameters/dif:Detailed_Variable
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:CategoryKeyword
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:TopicKeyword
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:TermKeyword
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:VariableLevel1Keyword/echo:Value
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:VariableLevel2Keyword/echo:Value
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:VariableLevel3Keyword
ECHO (1) /*/echo:ScienceKeywords/echo:ScienceKeyword/echo:DetailedVariableKeyword
ECS (1) /*/ecs:DisciplineTopicParameters/ecs:DisciplineKeyword
ECS (1) /*/ecs:DisciplineTopicParameters/ecs:TopicKeyword
ECS (1) /*/ecs:DisciplineTopicParameters/ecs:TermKeyword
ECS (1) /*/ecs:DisciplineTopicParameters/ecs:VariableKeyword
DCAT dct:keyword
FGDC (1) /fgdc:metadata/fgdc:idinfo/fgdc:keywords/fgdc:theme/fgdc:themekey
ISO (1) /*/gmd:identificationInfo/*/gmd:descriptiveKeywords/gmd:MD_Keywords[gmd:type/gmd:MD_KeywordTypeCode='theme']/gmd:keyword/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:descriptiveKeywords/mri:MD_Keywords[mri:type/mri:MD_KeywordTypeCode='theme']/mri:keyword/gco:CharacterString
Topic CategoryHigh level category enumeration used in ISODIF (1) /dif:DIF/dif:ISO_Topic_Category
DCAT dct:category
ISO (1) /*/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:topicCategory/gmd:MD_TopicCategoryCode
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:topicCategory/mri:MD_TopicCategoryCode
Distribution ContactContact information for the organization or individual that distributes the resource.DIF /dif:DIF/dif:Data_Center/dif:Personnel/dif:Role
ECHO /*/echo:ArchiveCenter
ECS /*/ecs:ArchiveCenter
DCAT dct:contactPoint
FGDC /fgdc:metadata/fgdc:distinfo/fgdc:distrib/fgdc:cntinfo
ISO /gmd:MD_Metadata/gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorContact/gmd:CI_ResponsibleParty
ISO-1 /mdb:MD_Metadata/mdb:distributionInfo/mrd:MD_Distribution/mrd:distributor/mrd:MD_Distributor/mrd:distributorContact/cit:CI_Responsibility
AbstractA paragraph describing the resource.

Note: This concept is called "Desciption" in Catalog Services for the Web.
DIF /dif:DIF/dif:Summary/dif:Abstract
ECHO /*/echo:Description
ECS /*/ecs:CollectionDescription
DCAT dct:description
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:descript/fgdc:abstract
ISO /*/gmd:identificationInfo/*/gmd:abstract/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:abstract/gco:CharacterString
Metadata Standard CitationThe name of the standard to which the metadata conformsDIF /dif:DIF/dif:Metadata_Name
FGDC /fgdc:metadata/fgdc:metainfo/fgdc:metstdn
ISO /gmd:MD_Metadata/gmd:metadataStandardName
ISO-1 /mdb:MD_Metadata/mdb:metadataStandard
Metadata Standard VersionThe name of the standard to which the metadata conformsDIF /dif:DIF/dif:Metadata_Version
FGDC /fgdc:metadata/fgdc:metainfo/fgdc:metstdv
ISO /gmd:MD_Metadata/gmd:metadataStandardVersion
ISO-1 /mdb:MD_Metadata/mdb:metadataStandard/cit:CI_Citation/cit:identifier/mcc:MD_Identifier/mcc:version


DIF for Data Discovery - Highly Recommended

The Directory Interchange Format (DIF) is a NASA metadata format used to create directory entries that describe scientific data sets. The attributes in the spiral below are highly recommended by the DIF standard. Additonal documentation is available via the following online references:

Source: Interactive Write a DIF Guide DIF standard specification

ConceptDescriptionDialect (Fit) Paths
Complete CitationComplete citation for the resource as a text blob.ECHO /*/echo:CitationForExternalPublication
ECS /*/ecs:CitationforExternalPublication
Resource ContactThe organization or person responsible for answering questions about the resource.DIF /dif:DIF/dif:Personnel[dif:Role='INVESTIGATOR']
ECHO /*/echo:Contacts/echo:Contact
ECS /CollectionMetaDataFile/CollectionMetaDataSets/Collections/CollectionMetaData/Contact[Role='User Services']
DCAT dct:contactPoint
ISO /*/gmd:identificationInfo/*/gmd:pointOfContact
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:pointOfContact
Online ResourceOnline Resource for the cited resourceDIF /dif:DIF/dif:Data_Set_Citation/dif:Online_Resource
DIF /dif:DIF/dif:Reference/dif:Online_Resource
ECHO /echo:OnlineResources/echo:OnlineResource/echo:URL
ISO //gmd:CI_Citation/gmd:citedResponsibleParty/gmd:CI_ResponsibleParty/gmd:contactInfo/gmd:CI_Contact/gmd:onlineResource/gmd:CI_OnlineResource
ISO-1 //cit:CI_Citation/cit:onlineResource/cit:CI_OnlineResource
InstrumentInformation about the instrument used to make the observations.DIF /dif:DIF/dif:Sensor_Name
ECHO //echo:Platforms/echo:Platform/echo:Instruments/echo:Instrument
ECS /ecs:Instrument
ISO /gmi:MI_Metadata/gmi:acquisitionInformation/gmi:MI_AcquisitionInformation/gmi:instrument/gmi:MI_Instrument
ISO /gmi:MI_Metadata/gmi:acquisitionInformation/gmi:MI_AcquisitionInformation/gmi:platform/gmi:MI_Platform/gmi:instrument/gmi:MI_Instrument
ISO-1 /mdb:MD_Metadata/mdb:acquisitionInformation/mac:MI_AcquisitionInformation/mac:instrument/mac:MI_Instrument
ISO-1 /mdb:MD_Metadata/mdb:acquisitionInformation/mac:MI_AcquisitionInformation/mac:platform/mac:MI_Platform/mac:instrument/mac:MI_Instrument
PlatformThe platform used to collect the observations.DIF /dif:DIF/dif:Source_Name
ECHO /*/echo:Platforms/echo:Platform
ECS /ecs:Platform
ISO /gmi:MI_Metadata/gmi:acquisitionInformation/gmi:MI_AcquisitionInformation/gmi:platform/gmi:MI_Platform
ISO-1 /mdb:MD_Metadata/mdb:acquisitionInformation/mac:MI_AcquisitionInformation/mac:platform/mac:MI_Platform
Temporal ExtentThe temporal extent of the resourceDIF /dif:Temporal Coverage
ECHO /*/Temporal/RangeDateTime
ECS /ecs:RangeBeginningDate
ECS /ecs:RangeEndingDate
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:timeperd/fgdc:timeinfo/fgdc:rngdates
ISO /*/gmd:MD_DataIdentification/gmd:extent/gmd:EX_Extent/gmd:temporalElement/gmd:EX_TemporalExtent
ISO-1 /*/mri:MD_DataIdentification/mri:extent/gex:EX_Extent/gex:temporalElement/gex:EX_TemporalExtent
Paleo-Temporal CoverageThe temporal extent for paleoclimate or geologic data.DIF /dif:DIF/dif:Paleo_Temporal_Coverage
Bounding BoxA bounding box for identifying a geographic area of interest

Note: This concept is called "Coverage" in the CSW Specification
DIF /dif:DIF/dif:Spatial_Coverage
ECHO /*/echo:Spatial/echo:HorizontalSpatialDomain/echo:Geometry/echo:BoundingRectangle
ECS /*/ecs:Spatial/ecs:HorizontalSpatialDomain/ecs:BoundingRectangle
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:spdom/fgdc:bounding
ISO /*/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:extent/gmd:EX_Extent/gmd:geographicElement/gmd:EX_GeographicBoundingBox
ISO /*/gmd:identificationInfo/srv:SV_ServiceIdentification/srv:extent/gmd:EX_Extent/gmd:geographicElement/gmd:EX_GeographicBoundingBox
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:extent/gex:EX_Extent/gex:geographicElement/gex:EX_GeographicBoundingBox
Place KeywordA comma separated list of key words and phrases that give the location of the resource.

Note: Some dialects include keywords, but they do not include mechanisms for identifying the type. In those cases it is difficult to unambiguously identify place keywords.
DIF /dif:DIF/dif:Location/dif:Location_Category
DIF /dif:DIF/dif:Location/dif:Location_Type
DIF /dif:DIF/dif:Location/dif:Location_Subregion1
DIF /dif:DIF/dif:Location/dif:Location_Subregion2
DIF /dif:DIF/dif:Location/dif:Location_Subregion3
DIF /dif:DIF/dif:Location/dif:Detailed_Location
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:keywords/fgdc:place/fgdc:placekey
ISO /*/gmd:identificationInfo/*/gmd:descriptiveKeywords/gmd:MD_Keywords[gmd:type/gmd:MD_KeywordTypeCode='place']/gmd:keyword/gco:CharacterString
ISO /gmd:MD_Metadata/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:extent/gmd:EX_Extent/gmd:geographicElement/gmd:EX_GeographicDescription/gmd:geographicIdentifier/gmd:MD_Identifier/gmd:code/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:descriptiveKeywords/mri:MD_Keywords[mri:type/mri:MD_KeywordTypeCode='place']/mri:keyword/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:extent/gex:EX_Extent/gex:geographicElement/gex:EX_GeographicDescription/gex:geographicIdentifier/mcc:MD_Identifier/mcc:code/gco:CharacterString
Spatial ResolutionThe nominal scale and/or spatial resolution of the resource.DIF /dif:Data_Resolution
ECHO /*/eos:AdditionalAttributes/*/eos:MeasurementResolution
ECS /ecs:LatitudeResolution
ECS /ecs:LongitudeResolution
ISO /*/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:spatialResolution
ISO-1 /*/mdb:identificationInfo/*/mri:spatialResolution
Temporal ResolutionThe smallest time step included in the resource.DIF /dif:Data_Resolution/dif:Temporal_Resolution
ECHO /*/eos:AdditionalAttributes/*/eos:MeasurementResolution
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:temporalResolution/gts:TM_PeriodDuration
Resource TitleA short description of the resource. The title should be descriptive enough so that when a user is presented with a list of titles the general content of the data set can be determined.DIF /dif:DIF/dif:Entry_Title
DIF /dif:DIF/dif:Data_Set_Citation/dif:Dataset_Title
ECHO /*/echo:ShortName>/*/echo:LongName
ECS /*/ecs:ShortName > /*/ecs:LongName
DCAT dct:title
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:citation/fgdc:citeinfo/fgdc:title
ISO /*/gmd:identificationInfo/*/gmd:citation/gmd:CI_Citation/gmd:title/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:citation/cit:CI_Citation/cit:title/gco:CharacterString
Quality StatementInformation about the quality of the data or any quality assurance procedures followed in producing the data.DIF /dif:DIF/dif:Quality
ISO /gmi:MI_Metadata/gmd:dataQualityInfo/gmd:DQ_DataQuality/gmd:report
ISO-1 /mdb:MD_Metadata/mdb:dataQualityInfo/mdq:DQ_DataQuality/mdq:standaloneQualityReport/mdq:DQ_StandaloneQualityReportInformation/mdq:abstract
ISO-1 /mdb:MD_Metadata/mdb:dataQualityInfo/mdq:DQ_DataQuality/mdq:report
Resource Access ConstraintsInformation about any constraints for accessing the data set. This includes any special restrictions, legal prerequisites, limitations and/or warnings on obtaining the data set. Some words that may be used in this field include: Public, In-house, Limited, Additional detailed instructions on how to access the data can be entered in this field.DIF /dif:DIF/dif:Access_Constraints
ECHO /*/echo:RestrictionFlag
ECHO /*/echo:RestrictionComment
ECHO /*/echo:Visible
ECS /*/ecs:AccessConstraints
DCAT /dct:accessLevel
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:accconst
ISO /*/gmd:identificationInfo/*/gmd:resourceConstraints/gmd:MD_LegalConstraints/gmd:accessConstraints/gco:CharacterString
ISO /*/gmd:identificationInfo/*/gmd:resourceConstraints/gmd:MD_LegalConstraints/gmd:otherConstraints/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:resourceConstraints/mco:MD_LegalConstraints/mco:accessConstraints/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:resourceConstraints/mco:MD_LegalConstraints/mco:otherConstraints/gco:CharacterString
Resource Use ConstraintsInformation about how the data may or may not be used after access is granted to assure the protection of privacy or intellectual property. This includes any special restrictions, legal prerequisites, terms and conditions, and/or limitations on using the data set. Data providers may request acknowledgement of the data from users and claim no responsibility for quality and completeness of data.DIF /dif:DIF/dif:Use_Constraints
ECHO /*/echo:RestrictionFlag
ECHO /*/echo:RestrictionComment
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:useconst
ISO /*/gmd:identificationInfo/*/gmd:resourceConstraints/gmd:MD_Constraints/gmd:useLimitation/gco:CharacterString
ISO /*/gmd:identificationInfo/*/gmd:resourceConstraints/gmd:MD_LegalConstraints/gmd:useConstraints/gmd:MD_RestrictionCode
ISO /*/gmd:identificationInfo/*/gmd:resourceConstraints/gmd:MD_LegalConstraints/gmd:otherConstraints/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:resourceConstraints/mco:MD_Constraints/mco:useLimitation/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:resourceConstraints/mco:MD_LegalConstraints/mco:useConstraints/mco:MD_RestrictionCode
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:resourceConstraints/mco:MD_LegalConstraints/mco:otherConstraints/gco:CharacterString
MediaMedia on which the resource is availableDIF /dif:DIF/dif:Distribution/dif:Distribution_Media
FGDC /fgdc:metadata/fgdc:dataqual/fgdc:lineage/fgdc:sinfo/fgdc:type
ISO /gmd:MD_Metadata/gmd:distributionInfo/gmd:MD_Distribution/gmd:transferOptions/gmd:MD_DigitalTransferOptions/gmd:offLine/gmd:MD_Medium/gmd:name/gmd:MD_MediumNameCode/@codeListValue
ISO-1 /mdb:MD_Metadata/mdb:distributionInfo/mrd:MD_Distribution/mrd:transferOptions/mrd:MD_DigitalTransferOptions/mrd:offLine/mrd:MD_Medium/mrd:name/cit:CI_Citation/cit:title/gco:CharacterString
Transfer SizeThe size of the digital resourceDIF /dif:DIF/dif:Distribution/dif:Distribution_Size
ECHO /echo:Granule/echo:DataGranule/echo:SizeMBDataGranule
ECS /ecs:SizeMBECSDataGranule
ISO /gmd:MD_Metadata/gmd:distributionInfo/gmd:MD_Distribution/gmd:distributionFormat/gmd:MD_Format/gmd:formatDistributor/gmd:MD_Distributor/gmd:distributorTransferOptions/gmd:MD_DigitalTransferOptions/gmd:transferSize/gco:Real
ISO /gmd:MD_Metadata/gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorTransferOptions/gmd:MD_DigitalTransferOptions/gmd:transferSize/gco:Real
ISO-1 /mdb:MD_Metadata/mdb:distributionInfo/mrd:MD_Distribution/mrd:distributionFormat/mrd:MD_Format/mrd:formatDistributor/mrd:MD_Distributor/mrd:distributorTransferOptions/mrd:MD_DigitalTransferOptions/mrd:transferSize/gco:Real
ISO-1 /mdb:MD_Metadata/mdb:distributionInfo/mrd:MD_Distribution/mrd:distributor/mrd:MD_Distributor/mrd:distributorTransferOptions/mrd:MD_DigitalTransferOptions/mrd:transferSize/gco:Real
Resource FormatThe physical or digital manifestation of the resourceDIF /dif:DIF/dif:Distribution/dif:Distribution_Format
ECHO /*/echo:DataFormat
ECS /ecs:PrimaryCSDT
ISO /*/gmd:distributionInfo/gmd:MD_Distribution/gmd:distributor/gmd:MD_Distributor/gmd:distributorFormat/gmd:MD_Format/gmd:name/gco:CharacterString
ISO /*/gmd:distributionInfo/gmd:MD_Distribution/gmd:distributionFormat/gmd:MD_Format/gmd:name/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:distributionInfo/mrd:MD_Distribution/mrd:distributionFormat/mrd:MD_Format
ISO-1 /mdb:MD_Metadata/mdb:distributionInfo/mrd:MD_Distribution/mrd:distributor/mrd:MD_Distributor/mrd:distributorFormat/mrd:MD_Format
Resource LanguageThe language of the resource.DIF /dif:DIF/dif:Data_Set_Language
ISO /*/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:language/gco:CharacterString
ISO-1 /mdb:MD_Metadata/mdb:defaultLocale/lan:PT_Locale/lan:language/lan:LanguageCode
ISO-1 /mdb:MD_Metadata/mdb:otherLocale/lan:PT_Locale/lan:language/lan:LanguageCode
Resource StatusThe status of the resourceDIF /dif:DIF/dif:Data_Set_Progress
FGDC /fgdc:metadata/fgdc:idinfo/fgdc:status
ISO /*/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:status/gmd:MD_ProgressCode
ISO-1 /mdb:MD_Metadata/mdb:identificationInfo/*/mri:status/mcc:MD_ProgressCode

xPath Note: The xPaths included in this table use several wildcards. // means any path, so //gmd:CI_ResponsibleParty indicates a gmd:CI_ResponsibleParty anywhere in an XML file. /*/ indicates a single level with several possible elements. This usually indicates one of several concrete realizations of an abstract object. For example /*/gmd:identificationInfo could be gmd:MD_Metadata/gmd:identificationInfo or gmi:MI_Metadata/gmd:identificationInfo and gmd:identificationInfo//*/gmd:descriptiveKeywords could be gmd:identificationInfo/gmd:MD_DataIdentification/gmd:descriptiveKeywords or gmd:identificationInfo/srv:SV_ServiceIdentification/gmd:descriptiveKeywords. Fit: The fit of the dialect path with the concept is estimated on a scale of 1 = excellent two-way fit, 2 = one-way fit or some other problem, 3 - extension required.

Page - Data Discoverability /Accessibility