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A combination of evolving technologies, economic circumstances, and the need to manage the increased flow of information culminated in the utilization of computer networks in libraries to enhance information retrieval and document delivery and facilitate access to resources. Computer networks have enabled librarians to streamline support services and reduce the costs of labor intensive operations. A computer network is a structure that makes available to an end user at one place some service performed at another place. Ever since computer users started accessing central processor resources from remote terminals three decades ago, computer networks have become complex, powerful, and versatile. Technically, computer networks have evolved from dedicated private networks to those utilizing multiplexed links or accessing hosts from multiple vendors. Geographically, computer networks have the capability to link several buildings, a few states or span the globe. Advanced telecommunications technology in concert with computer technology triggered the emergence of all sizes, shapes, and types of computer networks to enable terminals and/or users connected to the networks to communicate with each other. While libraries' needs are changing in the fields of video and voice communications, the most profound alterations are in the realm of data communications or telecommunications among computers and between terminals and computers. To cope with the mix of requirements for sharing resources ranging from bibliographic citations and cataloging and circulation records to grant proposals and publications, librarians in the 1980s are turning to a special form of computer network, the extended local area network or linked LAN, as a tool for connecting diverse communications equipment. A local area network is a facility providing data communications within a geographically limited area. Essentially, a local area network can bind together proliferating personal computers, terminals, host computers, and other communications equipment for information interchange. These local area networks can be connected into linked LANs or extended local area networks through fiber optic transmission in a dispersed geographical area for maximum communications efficiency. The dissertation, NETWORKING: CHOOSING A LAN PATH TO INTERCONNECTION, is about the mortar and bricks out of which computer networks are built. Special emphasis is placed on the process of designing, installing, and implementing local area networks and on the linkage of these LANs as a strategy for information management for multi type library consortia such as SEFLIN (SouthEast Library Information Network). Consisting of public and academic libraries in Southeast Florida, SEFLIN is responsible for promoting resource sharing and the dissemination of new knowledge in all areas of study for the 3.2 million residents of Florida's Broward, Dade, and Palm Beach Counties. SEFLIN participants include the Broward Community College Library, the Broward County Library System, the Florida Atlantic University Library, the Florida International University Library, the Miami – Dade Community College Library, the Miami-Dade Public Library, and the University of Miami Library. Scarcity of space, shrinking budgets, growing user demands and expectations, spiraling costs of materials and services, and price reductions in communications and computing equipment contributed to the emergence of multi type library networks such as SEFLIN for resource sharing. SEFLIN was formed to serve the needs of a mixed community of library users by supplying access to a full range of information resources and offering sophisticated support for a host of library and management function including online processing and cataloging, circulation control, serials control, fund accounting, statistical reporting, word processing and electronic mail. SEFLIN's primary mission is to link libraries in a common pattern of information exchange through the creation of an extended local area network or linked LAN. Sharing decision making data among public and academic libraries broadens the scope of sources and services available to the user community. Few areas in data communications much recent offering as technological innovation and local area networks. Local have seen as new commercial area network development has responded to the users' demand for greater transmission speed and capacity .Among user advantages provided by a LAN are enhanced reliability; faster response time; flexibility in applications programming; better supported facilities; and internetworking capabilities for multiple remote locations. Spanning short distances ranging from a few meters to several kilometers and involving high data rates and short propagation delays, local area networks are characterized by a variable number of devices requiring interconnection. As more and more materials become available and the costs of operations skyrocket, library professionals have to come to terms with the facts that not only is there not enough money around to be self-sufficient but often any semblance of self-sufficiency has become an impossibility. As a consequence, computer networks such as linked LANs are playing an increasingly important role in library activities. NETWORKING: CHOOSING A LAN PATH TO INTERCONNECTION is the result of efforts to explore the processes involved in developing a framework for interconnecting disparate computer systems in use by SEFLIN members in an extended local area network (LAN) or linked LAN based on the Open Systems Interconnection (OSI) Reference Model promulgated by the International Organization for Standardization (ISO). Within a multi-type library consortium such as SEFLIN, an extended local area network or linked LAN facilitates access to decision making data. A networking system such as Network Systems Corporation's HYPERbus which can be extended via private or public communications facilities such as Bell South T1 transmission technology, compatible Timep1ex devices, and Microtel's LaserNet, a fiber optic transmission system, into an extended local area network or linked LAN is a mechanism for facilitating the accomplishment of this mission. Inasmuch as HYPERbus has been utilized since 1984 by the Broward County Main Library, the major reference and research facility of the Broward County Library System, and can provide maximum performance networking capabilities for high speed digital data communications applications, NETWORKING: CHOOSING A LAN PATH TO INTERCONNECTION examines the feasibility of using HYPERbus as the basis for an extended local area network linking two SEFLIN participants, namely, the Broward County Main Library and the Florida Atlantic University Library. Developed by Network Systems Corporation, HYPERbus is a local area network implemented by Broward County's Information Resources Management Division in downtown Fort Lauderdale. Presently, HYPERbus is used to link the Broward County Main Library, the Broward County Governmental Center, the Broward County Courthouse, and the new jail facility. A multi-drop coaxial cable based system which transmits data at speeds up to 10M bps, HYPERbus features a flexible architecture capable of handling simultaneously diverse data rate, traffic types, and protocols and incorporating a variety of transmission media within the network. Moreover, HYPERbus can support extended span geographic distances using communication links. HYPERbus provides a data communications resource that is transparent to differences in communications media and equipment. As a consequence, network reconfiguration and expansion can be readily accomplished as new technologies, protocols, and user requirements emerge. The generic model developed in this dissertation for interconnecting two SEFLIN participants based on HYPERbus technology, however, is by no means exhaustive of all existing schemes; the field is presently so wide open that new schemes are being introduced constantly. Technological advances and economic pressures have stimulated interest in resource sharing through computer networking as an option for overcoming barriers in accessing information. The linking of computerized systems to enable one system to exchange data with another system is an essential and basic goal to any effective cooperative intersystem resource sharing effort. In this world of electronic communications, the future of computer networking which provides tailored data communications services to the user community is definitely on an upward climb as a consequence of such factors as competitive pricing, improved and faster transmission speeds, and conformance to standards devised by the International Organization for Standardization (ISO). NETWORKING: CHOOSING A LAN PATH TO INTERCONNECTION deals with designing and implementing a computer network for resource sharing and is intended for technical service and public service staff of the Broward County Library System who are using the building blocks of a local area network and still appear to be somewhat mystified by its information capabilities as well as for those who are not yet doing so. This dissertation examines the history of library involvement with networking, briefly reviews the history of library networking and automation, presents examples of library use of networking, and provides the user with the basic information needed for understanding networking technology and terminology. Further, NETWORKING: CHOOSING A LAN PATH TO INTERCONNECTION proposes an enhanced role for the Broward County Library System as a community information provider by using an extended local area network or linked LAN to actively pursue, organize, and make available to present and potential library patrons a range of information resources never before offered in today's information based society. |
