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? Public library users of wireless networks 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 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. How to get started 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 Bibliography "Secret Communications System: the fascinating story of the Lamarr/Antheil
spread-spectrum patent," by Chris Beaumont. 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:
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 From Solectek wireless network's press release on the
use of wireless to unite a number of Native American groups:
Prepared by GraceAnne A. DeCandido for the Public Library Association, August 12, 1999 ladyhawk@well.com
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