The wireless option.
Wireless LANs are perfect when installing cable is a problem. It's handy for temporary LANs, such as used by auditors or emergency sites when the expense of cabling can be covered in the higher cost of a wireless system.
Asbestos in old buildings can preclude rewiring. A New York bank wanted to install a LAN, but because the building had asbestos it was restricted. The bank faced drilling through an outer wall and running cable outside the building, enclosed to protect against the elements. Potential cost was $1 million for a 10-node network.
Activity and wireless LANs has stepped up lately.
* NCR's Radio Area Network sends data, via spread-spectrum technology, nine times faster than previous wireless LANs. RAN links computers in an 800-foot radius, transmitting data at 9.6 to 128 kb/s. The technology uses broad spectrum, low-power radio output (unlike a car radio which receives a narrow but powerful signal). Spread spectrum works well in open office environments or cubicles. Concrete walls are no obstacle; in fact, walls and ceilings help prevent intersystem interference. Fluorescent lighting? No worry. Like other wireless systems, RAN is transparent to Ethernet, token ring, or Arcnet.
* Telesystems' Advanced Radio LAN, Arlan, is a spread-spectrum network in two versions: 100, for multiuser applications with RS-232C async interface devices; and 400, NetWare compatible with IBM PC-Bus plug-in LAN cards. Arlan 100 network supports multiple RS-232C circuits at up to 19.2 kb/s each via a 200 kb/s packet-switched radio channel. Links are set up between remote, single-port network units and a multi-port central network controller, connected to host or other resource. Arlan 400 uses 230 kb/s packet-switched radio channel. Cards install directly in workstation.
* The new VeriFone TRANZceiver supports payment processing and other transaction automation applications. Range is 500-1000 feet. Typical applications: electronic payment processing, supermarket, drug chain, discount retailers, medical. Operates in bandwidths between 902 and 928 MHz. Supports seven radio frequencies, selectable by manual switch on each unit. Any LAN with RS-48 connection can use unit at speeds from 300 baud to 19.2 kb/s. Prices range from $350 to $585 depending on model.
* O'Neill Communications' LAWN (local area wireless network) offers spread spectrum at under $300 per node. Serves IBM or compatible PCs. Best suited to work-groups up to 20 users in coverage area of 10,000 square feet. Range is 600 feet.
* Photonics' Photolink LAN uses light beam that bounces off ordinary ceiling, to connect workgroup members in open or partitioned offices. Infrared LAN, which lists at $1195 per unit, can also link two buildings, with maximum range of 600 feet. Versions serve AppleTalk/LocalTalk LANs and RS-232 interfaces. Photonics targeted token ring and 270 interfaces this year. Ethernet version due early next year.
* Motorola is expected to announce Wireless In-Building Networks (WIN) built upon their experience in cellular and microwave. Look for 18-GHz-based system relying on an "intelligent" six-sector antenna to solve interference problem one would expect with so powerful a system. Should allow signal processing at a million connections per second via any of three switching modes: packet, fast packet, circuit. Will be transparent to standard protocols. Data scrambling will be added for security. When available (from Motorola's Radio-Telephone Sysltems Group), it should be fastest wireless system around.
* Harris is working with major computer company on wireless LAN. They want to solve capacity problems which separate simple uses from sending bulk data streams over wireless LANs. Look for that system to operate in the 900-MHz band, as approved by FCC for any wireless LAN operation.
* Cylink's new Digital Spread Spectrum Technologies (DSST) subsidiary will focus on wireless. They likely will position their LAN in FCC's Part 15 unlicensed 900-, 2400-, and 5700-MHz areas, linking hardware with DSST radio at 512 kb/s running full duplex.
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|Title Annotation:||local area networks|
|Author:||Harler, Curt; Tanzillo, Kevin|
|Date:||Nov 1, 1990|
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