Geoscape Australia

G-NAF

Metadata Statement

Metadata for the Metadata 
  • Metadata Identifier: G-NAF 
  • Scope: G-NAF Dataset 
  • Time: 18/08/2020 
  • Responsible Party: 
    • Contact Point: Michael Dixon 
    • Organisation: Geoscape Australia 
    • Position: Chief Data Officer 
    • Telephone: +61 2 6260 9000 
    • Delivery point: Unit 6, 113 Canberra Ave Griffith ACT 2603 Australia 
  • Access, Use, Security: Information supplied within the metadata may not be copied without referencing Geoscape Australia. 
  • Standard: ISO 19115-1 based on the ANZLIC/ICSM Metadata Working Group https://www.icsm.gov.au/sites/default/files/Poster%20-%20Best%20Practice%20for%20Datasets%20Metadata%20v1.pdf 
  • Language: English
Resource Metadata 
  • Title: G-NAF 
  • Identifier: G-NAF 
  • Abstract: The Geocoded National Address File (G-NAF) is Australia’s authoritative, geocoded address file. The dataset comprises official and in use address information using data sourced across the Governments of Australia.    
  • Purpose: To create a single national point of access to Australian address information. 
  • Time: The G-NAF dataset was originally released in 2004 and presently is published with updates quarterly in February, May, August, and November each year. 
  • Responsible Party: 
    • Contact Point: Geoscape Support
    • Organisation: Geoscape Australia 
    • Telephone: +61 2 6260 9000 
    • Facsimile: +61 2 6260 9001 
    • Delivery point: Unit 6, 113 Canberra Ave Griffith ACT 2603 Australia 
  • Access, Use Security 
    • Legal Constraints: G-NAF is available under licence from the Australian Government through https://data.gov.au/. The dataset is also available under licence from Geoscape Australia and authorised partners. Data usage is in accordance with the Geoscape Copyright Notice and Disclaimer available https://geoscape.com.au/legal/data-copyright-and-disclaimer/ 
    • Security Constraints: N/A 
    • Use Limitations: G-NAF is an index of Australian addresses and does not include detailed information describing land use, buildings or building locations.  
    • Releasability: The dataset should only be distributed in accordance with the licence under which it has been accessed
  • Extents: North Bounding Latitude: -8 South Bounding Latitude: -45 West Bounding Longitude: +96 East Bounding Longitude: +168 
North Bounding Latitude: -8 South Bounding Latitude: -45
West Bounding Longitude: +96 East Bounding Longitude: +168 
  • Reference System: 
    • Spatial Reference System: GDA94 and GDA2020 
    • Temporal Reference System: Gregorian calendar
  • Language: English 
  • Format: Various formats including psv, LYNX binary format, Oracle Data Pump, other formats may be available through distribution partners. 
  • Additional Information: A Product Description for the dataset is available from Geoscape Australia. Release Reports are made available at the time product updates are released. 
  • Linked Services & applications: Related products and services are available via www.geoscape.com.au G-NAF is also available via https://data.gov.au/  
  • Status: Complete  
  • Lineage:  G-NAF uses existing and recognised address sources (referred to as contributors) from the state and territory government land records and Commonwealth government organisations. A rigorous process is used that involves textual address comparison, matching and geospatial validation to provide both national consistency and national coverage. Maintenance activities are triggered through the receipt of updated address data from data contributors according to an agreed delivery schedule. At present, this schedule defines a quarterly update process. During the maintenance phase, contributed addresses are analysed and compared to existing records in G-NAF. This analysis and comparison gives rise to new records being inserted and existing records being updated or retired. The G-NAF maintenance pre-process takes the input files from reference datasets and contributor data and performs processing prior to data being processed by the G-NAF maintenance software. 
  • Pre-processing is used to describe the following activities:
    • Mapping from the contributor model to G-NAF model (with parsing as necessary).
    • Application of rules that make corrections to misspellings, abbreviations, and erroneous characters.
    • Application of updates to suburb data and road names propagating the changes through all affected parts of the data. 
    • The G-NAF maintenance software receives data from the pre-processing phase. All the contributed addresses from each jurisdiction are cleansed, compared, and merged into the normalised G-NAF maintenance model. 
  • The core maintenance processing consists of the following: 
    • Address scrubbing 
    • State-Locality validation and geocoding 
    • Street validation 
    • Street geocoding 
    • Address geocoding 
    • Merging (merge criteria and confidence levels) 
  • A further series of processing occurs for the following steps: 
    • Post merge processing (including validation processes) 
    • Primary / Secondary maintenance 
    • Alias / Principal maintenance 
    • Geocode maintenance 
    • Update address attributes (update attributes not in core processing) 
    • Update address links (i.e. contributor mapping, mesh blocks, default geocode) 
    • Verify G-NAF data (i.e. conformance with data model) Data export to integrated maintenance database 
  • For an address to be included in G-NAF, it must be a “complete” entry. Complete equals: 
    • Must include a matched locality 
    • Must include a street name 
    • Must contain either a valid number_first or a lot number 

Mesh Block data is sourced from the Australian Bureau of Statistics (ABS) and is part of their Australian Statistical Geography Standard (ASGS). 

  • Associated Resource: Further product documentation including a Product Description and a Release Report are published at the time of a dataset update.  
  • Maintenance: The G-NAF dataset is updated quarterly. 
  • Storage: The G-NAF dataset is managed by Geoscape Australia. 
  • Distribution: The dataset is available from multiple locations .
    • From Geoscape Australia and authorised re-sellers; 
      • Organisation: Geoscape Australia 
      • Telephone: +61 02 6260 9000 
      • Mailing address: Unit 6, 113 Canberra Ave Griffith ACT 2603 Australia 
      • Authorised Resellers: Available via https://geoscape.com.au/partners/ 
    • From the Australian Government 
      • https://data.gov.au/ 
  • Topic Category: Dataset metadata 
  • Keywords: Address, Physical Address, GNAF, G-NAF, Geocoded National Address File, Geocoding, National Address Management Framework, NAMF, Geocode.