The Z Texas Project Implementing Z39.50 to Improve Statewide Access to Library Catalogs and Other Online Resources William E. Moen William E. Moen, assistant professor in the School of Library and Information Sciences at the University of North Texas, is working with the Texas Z39.50 Implementors Group and the Texas State Library and Archives Commission to develop the Texas Profile for Z39.50. Dr. Moen can be reached at wemoen@jove.acs.unt.edu and more information can be obtained via his website at www.unt.edu/wmoen/.

Introduction

In August 1998, the Texas State Library and Archives Commission (TSLAC) hosted a meeting of librarians from around the state to identify strategies and new opportunities for using the ANSI/NISO Z39.50 information retrieval standard. Librarians' awareness of Z39.50 has increased in recent years and vendors' Z39.50 product and service offerings have become more plentiful. Recent evaluation studies of Z39.50 projects and implementations in Iowa (Blue Angel Technologies 1998), for the Big Ten universities and the University of Chicago (Hinnebusch 1998), for a virtual union catalog project in Canada (Lunau and Turner 1997), and elsewhere have indicated that simply installing a Z39.50 client or server will not lead to optimal search and retrieval results. Participants at the August meeting agreed to form a Texas Z39.50 Implementors Group (TZIG) and to map out strategy, tactics, and products that could assist Texas libraries in acquiring and using Z39.50. TZIG builds upon the experiences of recent projects and initiatives to improve search and retrieval from Z39.50­accessible library catalogs to develop a Texas solution for increasing Z39.50's utility in statewide searching of multiple library catalogs. The Z Texas Project is the name of TZIG's initiative to increase Z39.50 usability and effectiveness for Texas libraries and to lay a foundation for future sharing of online, digital information resources¹.

Increasing Awareness and Implementation of Z39.50

Within the state's library communities, there is increasing name-recognition and awareness of the national and international standard called Z39.50. This article is not intended as a tutorial on Z39.50, but a basic recap of some basic information about Z39.50 is warranted. (For a selection of introductory resources on Z39.50, see Moen and Lepchenske 1998.)

ANSI/NISO Z39.50-1995, Information Retrieval (Z39.50): Application Service Definition and Protocol Specification, is an American national standard developed under the auspices of the National Information Standards Organization (NISO). NISO is the only organization accredited by the American National Standards Institute (ANSI) to develop and maintain technical standards used in information systems and services used by libraries and publishers and other information providers. The original motivation for developing a computer­to­computer protocol for information retrieval was to link large bibliographic systems such as the Library of Congress, OCLC, and the Research Libraries Group to share bibliographic records. By the time the protocol gained NISO approval in 1988, an increasing number of people viewed Z39.50 as a general mechanism for searching and retrieving electronic informationwhether from library catalogs, technical databases, full­text online services, or other digital resources.

Z39.50 was developed to overcome problems associated with searching multiple databases (either remote or local). The standard sets out technical specifications for two computers to communicate for the purpose of information retrieval by providing a "language"– the grammar and vocabulary– that both computers use. Vendors of Z39.50 products implement the standard's specifications in computer software, both "clients" (used to perform a search) and "servers" (which provide access to the databases).

Using products that support Z39.50 makes it easier to retrieve information from local and remote electronic databases such as library catalogs. When working properly, a user never sees Z39.50. For example, with a Z39.50 client on a local integrated library system, a user interacts with a familiar search interface to search their own and other libraries' catalogs. To the user it appears as if the other libraries' catalogs were simply extensions of the local catalog.

As awareness of the utility of Z39.50 has grown, so too has the number of information providers that view Z39.50 as an important way to make their information resources accessible. The Library of Congress hosts the Z39.50 Maintenance Agency (http://lcweb.loc.gov/z3950/agency), and it compiles information about the many providers, initiatives, and projects that use Z39.50. The following is a sample of the initiatives and the types of resources accessible via Z39.50:

• Government Information Locator Service (GILS): uses Z39.50 for accessing government information
• Consortium for the Computer Interchange of Museum Information (CIMI): uses Z39.50 for search and retrieval of cultural heritage information
• Catalogue Interoperability Profile (CIP): A Committee on Earth Observation Satellites (CEOS) initiative that uses Z39.50 to promote interoperability among catalogs of earth observation data.

Most recently, the natural history museum community has demonstrated Z39.50 for accessing distributed repositories of biological specimen data. These initiatives suggest a new era in Z39.50 use and an increasing variety of digital information that can be accessed through Z39.50.

Complexity and Complications– It Seemed Too Good To Be True!

Providing access to various distributed electronic resources through a uniform interface is a compelling vision. Librarians perceive Z39.50 as an important strategic tool for reaching that vision. We appear to be at a moment of technology development when we can both envision integrated access to multiple and distributed electronic resources and begin to provide such access to our users.

The reality of most Z39.50 implementations, however, has yet to fulfill that vision. Searching multiple resources housed on different platforms with different designs and choices of access points presents challenges. Even when searching relatively similar resources such as online library catalogs, current Z39.50 implementations give results that often raise questions of reliability rather than increase confidence. Two important factors contribute to Z39.50 usability: 1) specific vendors' Z39.50 implementation decisions, and 2) the functionality of the local information retrieval system. (For a more detailed discussion of interoperability issues, see Moen 1998).

The primary area of concern for the TZIG is the first factor. Z39.50– even though it is a standard– contains many options and choices from which implementors can choose. Two vendors that build Z39.50 implementations may find problems in the ability of their systems to communicate meaningfully because of the manner in which each vendor implemented specific details and options from the standard. Even for basic searching of different library catalogs, interoperability problems arise because of different ways vendors implement key aspects of the standard. A useful approach for addressing these interoperability challenges is through the development of profiles.

A Texas Profile for Z39.50

Since the standard offers many choices and options from which implementors can choose, configuring Z39.50 clients and servers with a common set of specifications can lead to optimal results in searching and retrieving information. A profile is a document that identifies a subset of specifications and choices of options from the larger Z39.50 standard for a particular group of implementations (e.g., those for searching library catalogs). A profile reflects agreements among users (e.g., librarians) and Z39.50 implementors (e.g., library automation vendors) on a set of functional requirements needed by the users and the appropriate Z39.50 specifications to address those requirements. Profile specifications are voluntary, and librarians and vendors choose to use them because of the value the specifications bring to Z39.50 implementations.

A profile serves several purposes including:

• Offering specific guidance to vendors in configuring their Z39.50 client and server products
• Providing librarians with specifications to reference or use in procurements and requests for proposals.

A profile assists librarians in becoming smarter consumers of Z39.50 products, and it allows vendors to build Z39.50 products to a common configuration that can lead to economies of effort and scale in their Z39.50 development.

The Z Texas Project is TZIG's initiative to create a Z39.50 profile for Texas libraries. The Texas Profile is a major component of TZIG's strategy to improve Texas libraries' use of Z39.50. (See the sidebar on page 172 for complete Z Texas Project Scope, Goals, and Objectives.)

The resulting Texas Profile will provide librarians with clear guidance when purchasing and implementing Z39.50. As increasing numbers of Texas Z39.50 implementations share common specifications, the result should be improved search and retrieval performance between those implementations. Vendors can use the voluntary specifications in the Profile to configure and customize their Z39.50 products for the Texas library market.

Plans and Timelines for the Texas Profile

The initial phase of the Z Texas Project will focus on the requirements and specifications for basic search and retrieval between online USMARC library catalogs. Later phases of the Project will address requirements for searching other kinds of databases, such as those with full-text documents or images. Eventually, the Profile will contain several levels reflecting increasing requirements, with higher levels building upon the specifications of the lower levels to maintain compatibility. TZIG is also monitoring profiling developments at the international level to ensure that Texas specifications are aligned closely with an emerging international profile for searching library catalogs. Alignment of the Texas specifications with an international profile will increase the utility and cost-effectiveness of Texas Z39.50 implementations– not only will Texas libraries be able to interconnect, but the same Z39.50 implementation can provide Texas librarians and library users new access to global resources.

TZIG's timeline to develop its Profile is short. The current plan is to release the Profile in final draft at the Texas Library Association 1999 Annual Conference in April. Throughout the development period, TZIG will publicize its progress and release drafts of the Profile. Further, TZIG will actively solicit input from librarians, library automation systems vendors, Z39.50 implementors, and other individuals and groups interested in making Z39.50 a successful foundation for resource sharing in Texas. Testing of implementations that use the Profile specifications is anticipated for later in 1999. Demonstration of Profile­based implementations will encourage others (e.g., librarians and vendors) to adopt and use the Profile.

Summary

The Z Texas Project is our state's proactive response to resolving problems and pursuing opportunities for using Z39.50 as a technical foundation for near­term and long­term information resource sharing. TZIG, a voluntary and ad hoc group, is working on a Texas Profile that will reflect consensus on functional requirements for using Z39.50 and a set of Z39.50 specifications that can serve the State's library communities. We welcome participation in our meetings and through our electronic discussion group² to ensure that Z39.50 is part of a strategic foundation for resource sharing in Texas and integrated access to global digital resources.

Notes

1. Documents related to the TZIG, its meetings, and its membership can be found on the TZIG website maintained by TSLAC: http://www.tsl.state.tx.us/LD/ z3950/.

2. The Texas Z39.50 Internet List is the electronic discussion list for the Texas Z39.50 Implementors Group. For information on how to subscribe see instructions at http://www.tsl.state.tx.us/LD/z3950/list.htm.

References

Blue Angel Technologies, Inc. "An Evaluation of Z39.50 within the SILO Project," 1998. Available at: http://www.silo.lib.ia.us/bluang.html.

Committee on Earth Observation Satellites Protocol Task Team. "Catalogue Interoperability Profile," 1998. Available at: http://harp.gsfc.nasa.gov/~eric/cip-page3.html.

Consortium for the Computer Interchange of Museum Information Website, 1998. Available at: http://www.cimi.org.

Government Information Locator Service Website, 1998. Available at: http://www.gils.net.

Hinnebusch, Mark. "Report to the CIC on the State of Z39.50 Within the Consortium," 1998. Available at: http://www.cic.uiuc.edu/cli/z39-50report.htm.

Lunau, Carrol and Turner, Fay. "Summary of Issues Related to the Use of Z39.50," 1997. Available at: http://www.nlc-bnc.ca/resource/vcuc/ezarlsum.htm.

Moen, William E. "Texas Z: The Texas Z39.50 Requirements and Specifications Project. A Discussion Paper." Prepared for the Texas State Library and Archives Commission, 1998. Available at: http://www.unt.edu/wmoen/Z3950/TexasZDPAug98.htm.

Moen, William E. and Lepchenske, Teresa. "Z39.50: Selected List of Resources," 1998. Available at: http://www.unt.edu/wmoen/Z3950/BasicZReferences.htm.

National Information Standards Organization. ANSI/NISO Z39.50-1995, Information Retrieval (Z39.50): Application Service Definition and Protocol Specification. Bethesda, MD: NISO Press, 1995.

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