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Dayna, Xircom Find Right Size For Wireless

Xircom and Dayna are offering a short-range, moderate-speed wireless solution that spans the PC and Macintosh market, and uses 2.4-GHz spread spectrum and frequency-hopping technology. The best part about Xircom's CreditCard NetWave Adapter and Dayna's Serial Roamer is their small footprint. Where most adapters are Type II PC Cards connected to an externally mounted antenna box, this product has a sturdy small antenna tab directly attached.

Although these are short-range devices compared with others on the market, that does not necessarily limit their range of motion. Buying additional access points gives you virtually limitless range. Additional access points also serve to increase the overall bandwidth of the wireless network, and users can move between access points without even knowing it.

We had the Dayna Serial Roamers and an access point in our University of Wisconsin labs last year and found them reliable and very easy to use. However, we saw very slow performance. This has been corrected in the new versions, and you can expect speeds of approximately twice that of LocalTalk or around one-tenth that of a normal Ethernet adapter.

Only Intel-based machines can take advantage of the smallest PC Card footprint-a single Type-II PC Card. Because Apple has yet to release the card and socket services for its PC Card cage, Macintoshes require a small external case that houses the PC Card and then connects to the Macintosh serial port.

Intelligent Roaming and Site Survey

With the site survey application running under Windows95, we could see exactly what type of roaming activity was going on. The protocol used includes information regarding quality of the data pipe to the access point. The lower the quality of the channel, the more time the adapter spends searching for a better channel to an alternate access point. While the channel remains good, the adapter devotes all its time to data transfer.

For NetWare users, Xircom has also developed "intelligent roaming," which consists of a NetWare Loadable Module (NLM) for NetWare servers and a TSR for your DOS station, and allows for graceful roaming out of range. If the PC should leave range, the user is simply prompted to that effect. Upon returning into range, the connection resumes, complete with drive mappings. This will even hold if you put your machine on standby and head home.

CreditCard NetWave Adapter: $599 .
Available: Now .
Xircom, 2300 Corporate Center Dr.,
Thousand Oaks, CA 91320.
(800) 438-4526; fax (800) 775-0400.

DaynaCOMM Serial Roamer: $699.
Currently Shipping.
Dayna Communications,
849 W. Levoy Dr., Salt Lake City, Utah 84123.
(801) 269-7200;
fax (801) 269-7363.

Robert J. Kohlhepp can be reached at rkohlhepp@nwc.com.