UKOLN Z39.50 glossary

The American National Standards Institute coordinates, promotes and facilitates the US voluntary consensus standards system and its conformity assessment systems.

Application Protocol Data Unit, the means of communication between an origin and a target, specified in ASN.1.

Abstract syntax
representation of data that is independent of the physical encoding.

ASN.1: Abstract Syntax Notation 1 (ISO 8824)
A high-level data description language used for defining structures. ASN.1/BER is a platform-independent method of coding messages (PDUs) sent between Z39.50 client and server applications.

A descriptor applied to a search term that specifies how the term is to be treated when used for searching a target database (eg personal name or corporate name). Attributes are collected into sets and registered by the Z39.50 Maintenance Agency. BIB-1 was originally the only attribute set (designed specifically for searching databases of bibliographic records), but there are now also others.

BER: Basic Encoding Rules (ISO 8825)
convert abstract syntaxes to a specific transfer syntax.

a Z39.50 service added in version 3 which allows a client to discover information about a server, such as available databases, supported attribute sets and record syntaxes.

Extended Services
A set of services recognised by Z39.50 version 3 but which are not Z39.50 services themselves; they include saving a result set for later use, updating a database and item order.

The international protocol for interlibrary loan. There are two parts, a service definition (ISO 10160), which defines the ILL services made available to applications using the protocol, and a protocol specification (ISO 10161), which specifies the content of protocol messages and procedural rules for exchanging them.

International Standards Organisation.

ISO 2709
Standard format for bibliographic information interchange; it defines a record structure but does not prescribe the content. Although designed for data on magnetic tape, it is now also used for other media.

ISO 23950
This is the international standard - Z39.50 version 3 was accepted as an ISO standard in March 1997. The previous version was named SR (Search and Retrieve - ISO 10162/3).

Item order
One of the Z39.50 version 3 Extended Services, item order allows an origin to send a target a request for an item and to check the status of that order. The order may or may not be for an item resulting from a Z39.50 search.

An agreement specifying the use of Z39.50 to support a particular application, community, etc.

Serial Item and Contribution Identifier (ANSI/NISO Z39.56 1991). A variable length code that uniquely identifies serial items (issues) and contributions (articles within issues). The second version (199X) ballot period ends on 30 April 1996.

A character coding standard which supports the interchange, processing, and display of the written texts of the major trading languages.The current version contains 34,168 distinct coded characters derived from 24 supported scripts.

ISO/CCITT standard for electronic mail, facilitating the interconnection of messaging systems.
ISO/CCITT 'directory' standard designed to support the identification and location of systems, organisations and people, and to supply information about them. [CCITT has now been renamed ITU-T.]

Z39.50 ANSI/NISO (US) standard.
A retrieval protocol which allows client applications to query databases on remote servers, retrieve results, and perform other retrieval related functions.


WAIS (Wide Area Information Server)
A type of server that provides search access to text-based databases and ranks results based on relevance to the search. Based on Z39.50-1988 (version 1).

[UKOLN Z39.50 homepage]