The National Geospatial Data Framework (NGDF) is an initiative supported by a wide range of public and private sector organisations with a commitment to facilitate the 'unlocking of geospatial information'. In practice this commitment extends to providing:

• knowledge about what information exists
• access to information
• widespread use of information, and
• integration of information

Achievements in these areas will provide substantial benefits for the common good and will also go some way to supporting government policies in relation to open government and modernising government.

A major NGDF project under way is the NGDF Metadata project, which will set up a directory service to bring together through the Internet those who are providers of geospatial data with the users of such data. This project is funded by the Treasury Invest to Save Budget with a remit to develop the service by the end of March 2000. It is anticipated that beyond that date the service will expand and more data providers and therefore data users will become involved. The project and the service are seen as central to government’s role in making geospatial information more widespread.

The NGDF Gateway is a pivotal component of the NGDF Metadata Project and is designed to co-ordinate direct access to the distributed network of NGDF directory systems throughout UK. These individual directory systems or "nodes" can be implemented by any organisation (public or private) willing to provide on line access to their directory of Geographic Information data holdings. Directories may be for the exclusive use of an organisation, be a collective resource for an industry sector or be provided as a commercial service for users to ‘advertise’ their data holdings. Further details on the NGDF Gateway architecture are provided in the attached documents
NGDF Metadata Gateway Architecture V1.01 October 1999 ; and
NGDF Discovery Metadata Guidelines Version 1.1 June 1999 .

The business model proposed and being promoted by NGDF is based on the development of various distributed directories, which will be collectively searchable through the NGDF Gateway. In the first phase of the project, it is envisaged that most organisations will provide metadata to a restricted number of distributed directories, which will be linked and searchable through the NGDF Gateway.

The proposed Gateway shall provide the following technical functions and interfaces:

• User Enquiry
• Search
• Review
• Administration

The system will be use a web based user interface for searching and browsing the distributed directory network. The NGDF Gateway prototype provides an example of the types of search criteria that would be required on the search interface.

The Gateway is built upon a co-ordinated network of directory services. NGDF will be providing the administrative and support functions to ensure the sustainability and successful implementation of this network. The system will provide a simple interface for organisations to register details of their directory nodes to the Gateway administrator.

The NGDF Gateway will give access over the Internet to a wide variety of spatially related data owned by public and private sector. This data could include anything from topographical or geological maps to statistical information such as that from the census and health service.

The directory service will provide information (metadata) about the datasets. This metadata will include details about the data such as who the supplier is, what the geographical extent is, when the data was last updated, what the supply formats are etc.

The user of the gateway will be able to carry out keyword searches over the Internet to locate all of the datasets relating to that key word. It will do this by searching for the keyword in the metadata held for each of the datasets. Alternatively the user will be able to carry out searches based on geographical extent. For example the user would define an area of interest on a map of UK and the service would locate all datasets which hold information about that defined area.

Data providers will be provided with the NGDF metadata guidelines and encouraged to describe their data using these. This will mean that key word searches across the Internet will provide the best results possible.

The metadata produced by the data providers will be quality assured, initially at a basic level to validate that the information conforms to the NGDF metadata guidelines, but in the longer term the quality of the actual information itself will also be quality assured.

As well as enabling users to find out what data is available, we will also be setting up a help desk which will provide data providers with help preparing their metadata data, setting up maintenance procedures and guidance on establishing their own metadata services.

The initial delivery of phase one of the project is programmed for delivery April 2000.