This article originally appeared in TidBITS on 1991-06-03 at 12:00 p.m.
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Wireless Network News

by Adam C. Engst

Lots of little bits on the wireless front. People often say that a technology won't really catch on until IBM gives it the OK. If so, it's looking good for wireless networking. IBM recently tested a couple of wireless networking schemes, one a radio frequency method that uses an unlicensed band at 920 MHz, the other an infrared system. True to form, IBM has not said whether or not it will use this technology in any products, but it's fairly likely that something will show up in the portables that IBM is surely working on to run GO's PenPoint OS. Handheld tablet computers need network connections to make up for equipment often left out of the machine (like mass storage and various different types of communication ports), and nothing fits the bill better than a wireless network.

Connecting physically distant networks is usually difficult and expensive. However, Persoft Inc. has put together some (unnamed?) third-party hardware along with some custom software to allow two Ethernets to communicate via spread-spectrum radio waves up to 800 feet apart (so it's not all that far, it's a start anyway). Apparently the bridge supports data throughput at rates up to 2 Mbips, which isn't quite up to wired Ethernet's 10 Mbips, but it's still quite speedy. The package is a tad expensive at about $5000, but it's certainly cheaper than other sorts of wireless bridges that require licenses (such as microwaves) or line of sight access (like infrared).

Infrared communication may be line of sight, but it can be fast. Like the existing PhotoLink infrared networking scheme, BICC Communications' InfraLAN uses transceivers mounted high on walls or on the ceiling to transmit and receive the infrared signals. Unlike PhotoLink, InfraLAN is fast. BICC claims 4 and 16 Mbips token ring rates, which is a good speed. I don't know enough about the pros and cons of token ring versus Ethernet to make any judgements there, but BICC will be releasing an Ethernet version sometime soon.

California Microwave has a wireless LAN that does work with LocalTalk as well as Ethernet and any device that has an RS-232, RS-449/422, RS-485, or V.35 (whatever that is) port. It uses spread-spectrum technology, which allows it to broadcast omnidirectionally, unlike the infrared schemes, which are limited to line of sight transmission. Unfortunately, The Radio Link runs bit slowly, at 250 Kbips and a costs a fair amount at either $3450 (for one port at a lower frequency) to $5280 (for eight ports at a higher frequency). Still, it's a step in the right direction, since it transmits within a 500 foot radius inside, and supposedly up to 5 miles if nothing blocks the transmission.

No news yet on Apple's Data-PCS petition, but a couple of signs point toward an increase in wireless networking options. First, the FCC decided that when it gives out licenses for various parts of the radio spectrum it will give special treatment to applicants who want to do something innovative with the radio band. Personal communications certainly falls in that category, so I hope that something comes of it soon. The FCC has been busy, because it finally got around to creating the Technician class license for amateur radio use. The Technician class is limited to VHF and UHF frequencies above 30 MHz, but you do not have to learn Morse code to qualify for the license. So why is all this even mildly interesting? Many of the people who will fall into the Technician class want to use their computers to communicate with others over a packet radio network. I looked into the packet radio network a couple of years ago when the Technician class was first a proposal and decided that it was pretty neat, but that I just didn't have the background to get started with it for some time. If anyone who reads TidBITS knows about packet radio and would like to write an article, please let me know - I'd love to publish one.

Persoft -- 608/273-6000
BICC Communications -- 508/832-8650
California Microwave -- 408/732-4000
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