Structure of a Transfer Package

Metadata provides a common set of terminology and definitions for the documentation of digital geospatial data (CSDGM, Introduction). It is a required part of all Federal standards, and is required of all federally generated geospatial data per Executive Order 12906. The transfer of data always needs to be accompanied by copyright information, use restrictions, contact information, data lineage information, known data defects and a description of the geographic area that the data represents. The Content Standard for Digital Geospatial Metadata provides a uniform, consistent and well known way to express those things amongst others. Content Standard for Digital Geospatial Metadata

The Address Standard XML schema is a way of packaging address data such that only fields meaningful to the particular data transfer package need to be included. The nature of XML is that only meaningful data is included but the meaning of everything that could be included is documented. In addition, XML data transfer implementations can be extended without breaking existing implementations. Existing implementations will not understand the extensions but by definition will ignore them.

Data is produced by agencies possessing address information and consumed by those receiving the address data. Many agencies will be both producers and consumers at different times. The roles of producer and consumer describe, respectively, the activity at hand when exporting or importing address data.

Exporting Data

A data producer will follow these basic steps while implementing an export:

• Construct a logical map of local data fields into the equivalent Address Standard Content and Classification elements.
• Write programs or subroutines to split local fields into the Address Standard elements if necessary.
• Collect support information required by the CSDGM metadata into an accessible place.
• Optionally, write programs or subroutines to automate the CSDGM "Data Quality" tests documented in the Data Quality section of this standard.
• Write programs or subroutines to include the CSDGM support data into a complete and valid CSDGM document.

A data producer will follow these basic steps while creating a package of address data:

• Run the Data Quality tests and collect the reports into the CSDGM metadata.
• Set the "Publication Date" element of the CSDGM metadata to be the time the package will be published.
• Run the data remapping and splitting programs.
• Set the "DirectSource" element of the Address Standard to be the producers Id.
• Set the "AddressId" and "AuthorityId" elements of the Address Standard for any addresses created by the producer.
• Export the data into the Address Standard XML format.
• Transfer both the Address Standard XML document and the CSDGM document to another party.

Importing data

A data consumer will follow these basic steps while implementing an import:

• Construct a logical map of local data fields into the equivalent Address Standard Content and Classification elements.
• Write programs or subroutines to combine Address Standard elements into local data fields, if necessary.
• Create a place to store the CSDGM data from received packages.
• Optionally write programs or subroutines to automate the CSDGM "Data Quality" tests documented in the Data Quality section of this standard on the received data.

A data consumer will follow these basic steps while importing a package of address data:

• Receive both the Address Standard XML document and the CSDGM document from another party.
• Parse the Address Standard XML document into a working area.
• Parse the CSDGM XML document into a working area.
• Run the Data Quality tests and compare to the report in the CSDGM metadata recieved.
• Run the data remapping and combining programs.
• Import from the working area to the local production database.

When mapping local data fields into the equivalent Address Standard Content and Classification elements, or the reverse, it is important to understand that the Address Standard is set up to allow address producers to directly and unequivocally express the taxonomy of their own addresses. The Content and Classification sections provide a taxonomy to help parse addresses into descriptive elements.

For example, given an address such as 225 North Avenue Northwest Atlanta GA 30318, the Address Standard allows the the address producer to state that the word North is not a Street Name Pre Directional but is actually a Street Name. When stated by the actual addressing authority, it should be taken as factual and not converted.

Within other agencies, database design requirements might cause the address to be stored differently, but they should record the official form somewhere within their databases.

It is important, if distributing data received from other address authorities, that their taxonomy or parsing of addresses into elements be maintained and be reproducible.