
Most of our V.90 problems manifested themselves when making a connection, specifically when negotiating error correction. These problems created a high rate of errors that caused the modems to drop the call. In fact, the problem was so pronounced with an early Hayes Corp. Acura external and Optima PC Card modem that we were forced to exclude them from our tests. In many cases, however, modems with similar DSPs behaved similarly. Bear in mind that the modems we tested were not based on shipping code, and the manufacturers were still ironing out last-minute details of the V.90 specification.
Remember, too, that actual performance will depend greatly on the combination of client and server modems you choose. With specific initialization strings, you have some control over the modem's behavior, though even with the initialization strings you are not guaranteed V.90 connections.
Sitting Pretty: Internal/External Modems
While at first glance you might think internal and external modems are essentially interchangeable, they actually fit specific needs within the enterprise. External modems are commonly used for out-of-band management of remote network devices such as routers, switches and firewalls. Internal modems are better suited to the desktop, where they won't take up precious desk space or power outlets.
After sending out more than 100 invitational letters, we received and tested modems from ActionTec Electronics, Best Data Products, Boca Research, Digicom Systems, Hayes, LASAT Communications, MaxTech Corp., MultiTech Systems, NewCom, Shark Multimedia, Smart Modular Technologies, 3Com Corp. and Zoom Telephonics. In cases where we received multiple products from a single vendor, we tested only one modem, unless the firmware was demonstrably different.
After all the bits were passed, Boca Research's Tidalwave was our top choice. The Tidalwave had one of the most reliable V.90 connection percentages along with solid performance across all other connections. While the products sent by Digicom and MultiTech (ZBA) had a higher number of successful V.90 connections, their overall performance was not as impressive.
Smart Modular Technologies and ActionTec Electronics both delivered internal plug-and-play modems. The pair round out our top tier, with consistent performance and excellent features for the price.
Boca Research Tidalwave 56K External Fax/Data
Reliable performance, small footprint, easy-to-read LEDs and simple installation add up to make the Tidalwave our Editor's Choice. With a Rockwell DSP under the hood, the Tidalwave had some problems connecting to the 3Com I-Modem, but when hooking up to the Ascend MAX, connections were clean every time.
Based on our testing, we found that the Tidalwave made V.90 connections in the 40-Kbps range, occasionally falling back to V.34. The Tidalwave followed a connection pattern similar to most of the Rockwell-based units we tested, though its overall performance was more reliable.
The Tidalwave has front-panel LEDs so you can monitor its progress. Notably absent, however, is a 56-Kbps indicator, like you'll find on the MultiTech ZBA and ZDXV.
Smart Modular Technologies Rapid Transit 56KISA Data/Fax Modem
This easy-to-configure internal modem offers strong performance and a wealth of features for the remote user, such as plug-and-play capability, voice support and CallerID. At the extremely low price of $79, the Rapid Transit is a great value.
You'll need Microsoft Windows95 or newer to take advantage of the modem's plug-and-play capabilities--there are no jumpers to set the COM port or IRQs. The modem offers simultaneous voice and data when connected to other DSVD/V.70 capable modems.
ActionTec Electronics DeskLink Advantage v.90/56k Internal Voice/Fax Modem
If you have an open PCI slot, ActionTec's DeskLink might well be the modem for you. Like the Rapid Transit, the DeskLink DSP handles the modulation while the PC's CPU takes care of data compression and error control. This explains the requirement for a Pentium-class machine and PCI.
|