Superseded by Profile Release 2.0

Z Texas Profile:

A Z39.50 Profile for Library Systems Applications in Texas

Release 1.0

Stable Draft


Prepared by

The Texas Z39.50 Implementors Group (TZIG)


William E. Moen, Ph.D.

School of Library and Information Sciences

University of North Texas

Denton, TX 76203

April 20, 1999


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Table of Contents

1. Introduction to the Profile

2. The Z Texas Project

3. Functional Requirements

    3.1. Requirements for Release 1.0

        3.1.1. Requirements for Searching

        3.1.2. Requirements for Retrieval

        3.1.3. Other Requirements

   Holdings Information

    Browsing Indexes

4. Z39.50 Specifications

    4.1. Protocol Version

    4.2. Z39.50 Objects

    4.3. Z39.50 Services

        4.3.1. Init

        4.3.2. Search

   Attribute Set

        4.3.3. Retrieval: Record Syntax

    4.4. Diagnostic Messages

    4.5. Conformance

        4.5.1. Functional Area A: Online Catalog Search and Retrieval

   Functional Area A: Level 1 Searching

   Functional Area A: Level 2 Searching

        4.5.2. Functional Area B: Retrieval of Bibliographic Holdings Information

5. References

Appendix A: Definitions of Requirements for Level 1 and Level 2 Searches

Appendix B: Z39.50 Commentary--Z39.50 Keyword Searching of Bibliographic Systems

Appendix C: Open Issues

Appendix D: Potential Areas of Future Profile Work and Identified Future Requirements

Z Texas Profile:

A Z39.50 Profile for Library Systems Applications in Texas

1. Introduction to the Profile

The Texas Z39.50 Implementors Group (TZIG) developed the Z Texas Profile to identify a subset of specifications from the internationally- approved Z39.50 Information Retrieval Protocol (ANSI/NISO Z39.50/ISO 23950).  The Profile's specifications are intended initially for use in Z39.50 client and server software (hereafter referred to Z-client and Z-server) to support interoperable search and retrieval among library systems. As explained in Section 2: The Z Texas Project, the TZIG views the Z Texas Profile as an evolving set of specifications to address distributed search and retrieval of digital resources and to assist in resource sharing by Texas libraries. 

The TZIG is a voluntary and informal association of interested Texas librarians representing academic, public, school, and special libraries, and Z39.50 product developers and vendors.   The TZIG has identified future work areas for Profile development, including additional requirements not addressed in this Profile release.  Appendix D contains an indication of the future work areas and additional requirements. Appendix C contains a list of open issues still under discussion by the TZIG.

Release 1.0 addresses the basic requirements identified and discussed in Section 3: Functional Requirements. Those requirements support basic search and retrieval between USMARC online library catalogs, and the retrieval of holdings information. A key component of this Profile is to characterize the types of searching required by library users. To this end, the Profile defines specific searches and how the semantics of those searches will be expressed in the vocabulary of Z39.50.

The Z Texas Profile is intended to be aligned with the specifications being discussed for an international Z39.50 profile for library systems applications. This Profile builds upon the experience of other profiling efforts addressing interoperability for library catalog searching and the development of virtual union catalogs. In particular, the following efforts informed the Z Texas Profile:

The structure of the Z Texas Profile is modular and allows the future specification for separate but compatible requirements involving a range of applications useful to librarians and library patrons. The TZIG envisions future releases of this Profile to address other requirements such as search and retrieval from full-text databases, searching across other information resources such as museums, government, archives. etc. Such requirements will use features of Z39.50 not profiled in Release 1.0.

Release 1.0 specifies two Functional Areas:

  • Functional Area A for search and retrieval among USMARC online catalogs
  • Functional Area B for retrieval of bibliographic holdings information.

Z39.50 specifications and conformance requirements are detailed for each Functional Area.  Future functional areas that currently being considered include full-text database search and retrieval, item ordering, catalog update, etc.

2. The Z Texas Project

The Z Texas Project is an initiative to increase Z39.50 utility and effectiveness for Texas libraries and lay a foundation for future sharing of online, digital information resources. For information about the Z Texas Project, please visit the Project's website at: .

The TZIG has identified three Project goals:

  • To improve and broaden Texas citizens’ access to networked information resources in Texas and beyond.
  • To improve Texas librarians’ understanding of Z39.50 and their capability to acquire and set up Z39.50 Z-clients and Z-servers.
  • To establish one possible technical foundation for future sharing of the information assets of Texas.

The Z Texas Profile reflects consensus on functional requirements for using Z39.50 and a set of Z39.50 specifications that can serve the State’s library communities. Implementations that conform to this Profile can significantly improve Texas libraries’ use of Z39.50.

3. Functional Requirements

In developing the Profile, the TZIG first identified a set of functional requirements to be supported by Z39.50 implementations. The functional requirements will evolve over time as Texas implementors see new opportunities for distributed search and retrieval using Z39.50. For example, expanded use of the Generic Record Syntax (GRS-1) will be required to retrieve non-MARC information resources. This section identifies the functional requirements that informed specifications for Release 1.0 of the Profile.

3.1. Requirements for Release 1.0

The basic requirements for Release 1.0 focus on search and retrieval between online USMARC library catalogs. This reflects the makeup of the TZIG in Fall 1998; participants were primarily representatives from Texas libraries, and the requirements of this group are the basis of this Release. The following sections detail the requirements for searching and retrieval identified by the TZIG.

3.1.1. Requirements for Searching

The TZIG identified several categories of searching and developed requirements for two categories of searching in Release 1.0. Appendix A includes the Definitions of Requirements for Category 1 and Category 2 Searches. Category 1 can be considered a set of core searches, and Category 2 can be considered a superset of Category 1 searches with addition of more specialized searches (e.g. inclusion of call numbers). Other categories of searching may be defined in the future. Specific local systems may not support all types of searches defined for Release 1.0. The TZIG considers these searches, however, to provide basic functionality that all local systems should support.

Category 1 searches include common author, title, subject searches that might be used by patrons and librarians. The following summarizes Category 1 searching requirements:

  • Author searches for expressing queries that include an established name heading as well as queries that include names not under any authority control
  • Title searches include exact match on title (i.e., title proper) as well as keyword searching of titles
  • Subject searches include exact match on subject heading as well as keyword searching of subject fields and subfields
  • Keyword searches against author, title, subject, and other common access points (see Appendix B for Commentary on Keyword Searching of Bibliographic Systems)
  • Support for Boolean searching using AND, OR, NOT
  • Support for right truncation of search terms.

Category 2 searches include all Category 1 searches and more specialized requirements of patrons and librarians (e.g., catalogers, bibliographers, acquisitions, etc.). The following summarizes Category 2 searching requirements:

  • Inherit all requirements from Category 1 searching
  • Support for standard number searching
  • Support for call number searching
  • Support for searching based on date, format, language, and audience
  • Support for proximity searching.

Category 1 and Category 2 support common online catalog searching activities. By specifying two categories of searching, the TZIG promotes its goal to lower libraries' entry barriers for implementing Z39.50 while safeguarding interoperability.

Many OPACs currently allow users to browse indexes.  This is a useful feature, often used in conjunction with known-item searching. Browse-based searching can assist users in improving their selection of terms for the query.  Such browse-based searching can be seen as an alternative searching strategy for Category 1 and 2 (see, Browsing Indexes).  

3.1.2. Requirements for Retrieval

Release 1.0 addresses retrieval of bibliographic records from USMARC online databases. This implies very basic retrieval requirements; Z-servers must return brief and/or full forms of bibliographic records in USMARC format.  The TZIG is aware, however, that librarians and other users are interested in accessing more than bibliographic data. Such access will require other structures for retrieval likely to be accommodated through the Z39.50 record syntax, Generic Record Syntax (GRS-1).  Release 1.0 specifies the retrieval of holdings information using the OPAC/Holdings Schema, which requires support for GRS-1 (see .

3.1.3. Other Requirements

The TZIG focused its initial attention for Z39.50 specifications on searching, but it recognizes other important requirements. Of particular interest in Release 1.0 is to address the retrieval and display of bibliographic holdings information. See Appendix D for other areas of potential development and specification. Holdings Information

Identifying which collections contain certain information resources is a key factor in creating an infrastructure for resource sharing among libraries.  Librarians require holdings information for resource sharing, and patrons need similar holdings information for knowing where to go to use or borrow a resource.  The holdings information should provide sufficient identification and description of an item to give the user adequate information to make a decisions about requesting or retrieving the item.  For further information about the Z39.50 and retrieval of holdings, see a discussion paper prepared for the TZIG, Handling Bibliographic Holdings Information in Z39.50:

Implications for the Z Texas Profile
(Moen, 1999).  Browsing Indexes

Librarians and patrons often use a browse function on a local system to identify appropriate search terms to put in a query.  Searching term lists (or indexes) can enhance known-item searching.  Browsing indexes is a requirement for Z39.50 implementations.

4. Z39.50 Specifications

This section identifies the Z39.50 specifications to support the functional requirements identified in Section 3.

4.1. Protocol Version

The Profile addresses requirements related to Version 2 and Version 3 of Z39.50-1995.  All implementations are encouraged to use Version 3, but in the short-term, conformance to certain specifications prescribed by this Profile is available to Version 2 implementations.  Section 4.5 details specific requirements for conformance for each of the Versions.

4.2. Z39.50 Objects

The Profile addresses the following Z39.50 objects by reference to registered Object Identifiers (OIDs). For information on Z39.50 OIDs, see the Z39.50 Maintenance Agency's Definitions and Z39.50 Registry of Object Identifiers (see also Z39.50 Maintenance Agency).



Bib-1 attribute set


Bib-1 diagnostic set


USMARC record syntax


GRS-1 record syntax


OPACS/Holdings Schema

[to be assigned]

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