PLA Tech Note: Wireless Networks

Wireless Networks: Unplugged, and Play

In the early 1990s, there was a flurry of publication in both the library and trade press about wireless networks. The technology was there, but it was not cheap, and not easy. Now in the late 90s, wireless networks have become both easy and inexpensive: their use in public libraries, however, has not yet trickled down to publication, either in print or on the Web. This Tech Note makes use of interviews with librarians and systems managers who are using wireless in their libraries, as well as some technical and trade publications.

What is a wireless network?
A wireless network provides access to multiple computers, databases, the Internet, the library OPAC throughout a building or cluster of buildings. A wireless LAN (Local Area Network) functions within a building and requires a sending unit, a receiving unit, and pc cards for laptop access; its range may be 1000 meters. A wireless WAN (Wide Area Network) requires roof antennas for distance. WANs can cover a range of up to 24 miles, and are beginning to be used across campuses and towns.

Public library users of wireless networks
Users of wireless networks in public libraries are certainly enthusiastic. The Portage County Public Library in Wisconsin, in collaboration with the University of Wisconsin Stevens Point, uses wireless to obtain access to the Internet, and has done so since 1997. When Jeff Baskin, director of the William F. Laman Public Library in North Little Rock, Arkansas was asked why his library had a wireless network, he said, simply, "cost!" Housed in a 1960s poured concrete building that made rewiring or cable access both difficult and expensive, the library found, about six months ago, that wireless technology had reached the point where it would solve a number of intractable problems, and do so in a cost-effective way. Wireless is an excellent solution for older buildings, landmark structures, and places where removing walls might expose asbestos or simply be prohibitively expensive.

Within Laman Public Library, internet access, databases, and the library OPAC are all accessible via the wireless network. Laptop computers are available to users in the library, so they can sit anywhere in the building and access not only electronic media but be physically near whatever printed materials they want or need. Besides connecting them to all these resources, the wireless network also enables printing from any of the laptops to the laser printer at the Reference desk. "I want to make technology work hard for us, and this [wireless network] saves dollars," Baskin emphasized.

Just outside Atlanta in Smyrna, Georgia, Michael Seigler tells a similar tale. "It is so easy," he enthused, of the Smyrna Public Library wireless network. Internet access, the catalog, and other materials are accessible on four free-standing workstations in the library.

Baskin notes that wireless technology wasn't up to his needs even so recently as a year ago. However, the push for wireless now seems to be in the direction of what the tech magazines call SOHO: the Small Office/Home Office market. That kind of accessibility and price works for public libraries, too.

Although it is an academic rather than public library setting, the wireless network setup in the Division of Library and Information Science, St John's University, Jamaica, NY also illustrates wireless's flexibility and utility. The Information Technology Office at SJU wanted to build some experience with wireless, and chose DLIS because it had only two classrooms and two small public areas. Laptops were purchased, nodes were installed, and furniture more suited to such use was obtained. James Benson, dean of libraries at SJU, noted that not only is it an advantage to be able to take the computer where you want to go, but that wireless solves much of the infrastructure problem in older buildings where it is difficult to add power, cabling, or wiring to existing structures.

Searching for Hedy Lamarr
A key component of wireless data technology, from cell phones to wireless networking systems, comes from the development of an idea patented in the 1940s by the actress Hedy Lamarr and the composer George Antheil. Their concept of frequency-hopping is the basis for spread-spectrum radio systems.

This may be described, in wildly abbreviated form, thusly: there are three standards for wireless technologies (802.11), DSSS (Direct Sequence Spread Spectrum communications), FHSS (Frequency Hopping Spread Spectrum) and infrared. Vendors in this field offer several kinds of products using these technologies. In FHSS, "short bursts of data hop from one frequency to another based on a predetermined pattern." Transmitter and receiver synchronize these data. Because of the constant shifting of frequency, there's less interference and the data are difficult to intercept. DSSS produces a redundant bit pattern (also called a chip) for each bit of data so that if one or more bits are damaged, original data can be recovered without being retransmitted. This information is based on Peter Ruber's article in Network Magazine, which goes into further technical detail.
This, of course, may be rather more than you wanted to know.

How to get started
Larry Glover, systems manager for Laman Public Library in North Little Rock, Arkansas, walked through the process his library went through to institute their wireless network. After locating a few wireless vendors via search engines, he examined their specifications as listed on their web sites. Others strongly recommend a site survey by the vendor to ascertain specific needs. Glover then purchased the sending unit, which is the size of a small answering machine. He also purchased receiving units - his have four ports each, so that four desktops can be connected to the wireless network through each one - and pc cards for the library laptops. The units have a range of a thousand meters, above standard, says Glover, and required no reconfiguration for Win98 or NT (his open VMS OPAC required a bit of adjustment). The entire cost for the wireless LAN setup was under $5000. Libraries own the equipment they purchase, and FCC licenses are not required.

Wireless WANs, which require roof antennas and have a range of 8-24 miles, are of course more costly, but far less so than rewiring and cabling costs. A school district in Arizona maintains a wireless network over several schools and administrative offices for about half what a wired network would have cost them.

Wireless networks offer a cost-effective and seamless solution in places where older construction, landmark status, space considerations, or structural difficulties make wired access expensive and troublesome. Wireless networking seems poised to become a useful tool in the quest to provide access in public libraries, and Hedy Lamarr can add another string to her bow.

Some wireless vendors

Bytes Without Wires: Wireless LANs and WANs in Libraries. LITA Emerging Technologies Interest Group at ALA New Orleans, June 27, 1999.
Jim Barrentine's Powerpoint presentation, available on this site, is a clear outline of everything you want to know. It is, as is the way of Powerpoint, an outline only, so details and full accounts are not there. His diagrams, however, are a nice visual delineation of what happens in a wireless network setup.

"Secret Communications System: the fascinating story of the Lamarr/Antheil spread-spectrum patent," by Chris Beaumont.
This starts almost like a fairy tale: "Many years ago, on the eve of World War II, a well-known actress of the day and my father, an avant-garde American composer, while at a dinner party, thought up an interesting scheme to control armed torpedoes over long distances without the enemy detecting them or jamming their transmissions." Hedy Lamarr and George Antheil did indeed patent a wireless transmission system, and were awarded an Electronic Frontier Foundation award (posthumously, in the case of Antheil) a few years ago.

Network Magazine's June 1999 issue is all about wireless technology. Some of this is fairly technical, but all of it is worth reading. It includes:
Elizabeth Clark's "Pulling the Plug on the Local Loop"
Peter Ruber's "Wires Not Included"

WLANA: the Wireless LAN Alliance, a nonprofit consortium of wireless LAN vendors. A detailed "Introduction to Wireless LANs" carries the reader through the technical explanation.

The Wireless Libraries Homepage
While many of the links on this page are no longer operable, it does have a bibliography, and host Dale Foster expects to update it shortly (its last update was in the autumn of 1998).

From Solectek wireless network's press release on the use of wireless to unite a number of Native American groups:
"The Solectek wireless network has literally saved us from going over the river and through the woods, not to mention crossing the railroad tracks and several highways," said Terry Honeycutt, MIS Coordinator for the Isleta Pueblo in New Mexico. Email and internet access were made possible via this wireless network over 211,000 acres.

Prepared by GraceAnne A. DeCandido for the Public Library Association, August 12, 1999


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