Integrating other directories

Overview

Because the ASDD is based on the Z39.50 search and retrieve protocol (ISO 23950) any other networked directory system and the ASDD can inter-operate.

The ASDD search and retrieve overview explains ASDD Z39.50 search, retrieve, and present. Please read that for background understanding.

Any one collection of metadata (database or documents) can be indexed in different ways to form many different "metadata repositories" that are available for searching by a single Z39.50 server. Each Z39.50 server can also respond to one or more Z39.50 "Profiles" and "Attribute Sets" to allow searching of the same collection of metadata by many different user communities. There is no need to replicate the data - manage once, view many.

A single Z39.50 server can be the front-end to many different "metadata repositories" behind the scenes (relational database or document collection). Importantly, this enables the custodian to leave their existing document management systems in place and simply install a front-end interface to index and serve the metadata.

Many interfaces for different user communities can be configured to interrogate the same set of Z39.50 servers. The US Geospatial Data Clearinghouse gateway interface can search the ASDD nodes.

Inter-operable

The main components of the Z39.50 solution are described in other documentation. You will need to be familiar with these in order to understand how integrated directories can be built.

• Z39.50 Profiles
  • identifies a set of base standards for a particular metadata community
• Z39.50 Attribute Sets
  • Z39.50 queries are composed by a client or gateway using "Attribute Types", "Attributes", and search "Terms"
  • the "Use Attributes" define which metadata element to search against
  • standard attribute numbers are mapped to the relevant metadata elements at each particular metadata repository
• Element Sets
  • allow the client to specify which elements from a metadata record should be presented
• Record Syntaxes
  • specifies the format in which the client wants to see the metadata (HTML, text, XML)

Possible integrated directories

• Australian Antarctic Data Centre (AADC)
  • Needs to be able to serve one view of the metadata to the ASDD/GEO world and another view to the DIF (Directory Interchange Format) world and the Global Change Master Directory