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[ Go to October 1997 Table of Contents ]
WinLab Reviews
-- by Cynthia Morgan and Joel T. Patz
About the only thing you can say for sure about 56K modems is they don't live up to their name. 56K modems promise to rocket you into cyberspace at speeds of up to 56Kb per second over standard analog phone lines. That sounds like a big boost over the previous speed limit of 33.6Kbps. How do these new modems deliver on their promise? To find out, we tested six of the first 56K modems to hit store shelves. But the performance reported here is a composite of best and worst line scenarios we could find. It's not absolute-the quality of your phone lines and your ISP's equipment will affect 56K transmission dramatically-but should give an idea of relative performance of each device. That's bound to improve as new drivers are released. Just how big a boost you get from a 56K modem depends on the quality of your lines and the equipment on the other side of the connection. We spoke with a communications engineer who estimates that 56K modems will exceed 50Kbps reliably on only a small percentage of the public switched telephone network-the analog phone lines most U.S. residents use for modem calls. In our tests, modem speed dropped by as much as 60 percent when poorer lines were used for the same connections. At one test site in Seattle, we were unable to achieve more than 31.2Kbps with any of our test modems. A few blocks away, where lines evidently were less impaired, the same devices connected at 44Kbps to 48Kbps. Another factor limiting the speed of the new devices: The Federal Communications Commission has restricted the power output of service providers' modems, so downloads are effectively capped at 53Kbps. Connection quality is also an issue. Our tests showed dropped or failed connections in as many as 12 percent of our attempts, while older modem drop rates are usually between 3 percent and 4 percent. That can be aggravating in the middle of a large download. Only one modem, the U. S. Robotics Sportster 56K Faxmodem, gave us better-than-average connection success. All 56K modems follow one of two incompatible standards: K56flex (from Lucent Technologies and Rockwell Semiconductor Systems) or x2 (from U.S. Robotics) In our tests, x2 modems generally connected at speeds of 40Kbps or better about 44 percent of the time on all lines tested, but they achieved a connection speed of 50Kbps or faster only 20 percent of the time. In comparison, K56flex modems reached 40Kbps about 59 percent of the time, but exceeded 50Kbps only 10 percent of the time. A high initial connection speed, however, doesn't always translate into continued fast throughput because a modem adjusts its speed to accommodate changes in line quality. Our x2 devices dropped speed, sometimes to less than 19.2Kbps, more often than the K56flex units, resulting in more varied scores overall, especially at 50Kbps or higher. Although both standards use the same technology, they won't talk to each other at 56K speeds. If your ISP supports K56flex and you own an x2 modem, you'll never see the fast connections promised by 56K. When standards solidify early next year, many of these problems should be resolved. That's one reason to choose a 56K modem that can be software-upgraded-of the modems reviewed here, all but the Motorola unit can. However, acknowledging that such upgrades don't always work, Motorola and U.S. Robotics offer to replace the entire unit once the final 56K standard is in place. The units we tested supported a variety of other modem standards: MNP levels 2 through 4 and V.42 error correction, V.42bis and MNP 5 data compression, and ITU-T V.34, V.32 and V.32bis. All can send and receive data at 33.6Kbps, send and receive faxes at 14.4Kbps, and support the industry-standard Hayes AT command set. K56flex modems Boca 56K MD56E Boca's 56K MD56E Internet modem sports eight status lights on the front, with line and phone jacks and the power switch on the back. The unit supports Caller ID as well as the V.80 videoconferencing standard. Included in the software bundle are QuickLink MessageCenter (for Windows 3.1 and Windows 95), Data Secure Lite (for restricting access to your e-mail, data files and general desktop applications) and sign-up kits for AT&T WorldNet (which include five free hours and Internet Explorer 3.0), America Online and CompuServe. About 6 percent of our trials, on average, resulted in dropped connections, and overall download times were on the low side (see chart). The Boca's initial connection speeds were also below average. On the plus side, this device tended to hold a transmission speed throughout the session better than most. Hayes Accura 56K The Hayes Accura 56K modem, from a company long associated with modem standards, sports eight status lights on the front of the unit. On the back are the power connector and power switch, RJ-11 line and phone jacks, and the serial port connector. Hayes includes a CD-ROM with an online reference manual, and sign-up kits for America Online, CompuServe, Netcom (which includes Netscape Navigator 3.0), Prodigy and Sprynet. Hayes also provides Quarterdeck's IWare InternetSuite 2 and WebTalk, as well as Smartcom Message Center LE communications software and MindQ's Internet Online tutorial. The Accura carries a two-year warranty, extended to five if you register the unit within 90 days. Unfortunately, the Hayes turned in the worst performance of all the modems tested, whether connected to clean or "dirty" lines. For example, on our impaired-line tests it rated only 30.3Kbps, while on ideal-line tests it connected at 43.1Kbps-not a great score. The Hayes also had problems with dropped connections. In our trials, 12 percent of all impaired-line connections failed, while 5 percent of ideal-line connections failed, for an average rate of 8.5 percent. Average download times were at the bottom of the heap. Motorola ModemSurfr 56K Six modem status lights are on the front of Motorola's ModemSurfr 56K, while the serial port, power connectors, and RJ-11 line and phone jacks can be found on the back of the unit. There is no power switch. The modem ships with drivers on diskette and a CD-ROM with an Epoch Internet sign-up kit. Until recently, Epoch was one of the few nationwide service providers to offer K56flex. Also on the CD-ROM is product documentation in Adobe Acrobat format, as well as Trio's fax and data Communications Suite 5.1. The unit offers one of the best software installations we've seen for a communications device. The Motorola modem offered the best performance of our K56flex units. Our 0.5MB file download was the fastest of all the tested modems, and the 1.5MB download was the fastest of all the modems under ideal line conditions. The Motorola was more stable than most modems tested, returning a 4.5 percent overall dropped-connection rate and consistent connection speeds. x2 modems Cardinal Connecta 56K Cardinal's Connecta 56K is unusual in that it offers a volume control as well as a power switch on the top of the unit, along with seven status lights. The standard serial port, power connector, RJ-11 jacks and dip switches are on the back. The unit comes with a stand that allows it to be placed vertically in tight spaces. In addition to two free months of Internet access through Sprynet, the Connecta offers a wealth of software on CD-ROM, including net.jet, The Electronic Internet Bookshelf, Connected Online Backup (for offsite data backup and recovery), SurfinShield (a personal firewall against hostile Java applets), TeleVox (Internet telephony), ViruCide Plus, Sidekick 97, Internet Utilities 97 and more. The Connecta turned in better-than-average performance, giving us an average connect speed of 33.3Kbps for impaired line tests and a very good 46.4Kbps for ideal-line connections. The Connecta's average drop rate, at 6.5 percent, was on the high side, even in this crowd. Its transmission rates were more stable than most, and it provided the best of all the download times over the impaired line for our 1.5MB file downloads. Global Village TelePort 56 x2 The Global Village TelePort 56 x2 fax/modem sports a compact design measuring 1 by 3 by 5.6 inches. There's a built-in serial cable, which could be a concern if there are problems with the cable down the road. Three status lights (activity, power and connection) decorate the lower front of the unit, and the RJ-11 line and phone jacks, power connector and power switch are on the back. On the CD-ROM you'll find FaxWorks software, an America Online sign-up kit and GlobalTransfer Lite, a receive-only file transfer program. The CD also contains all hardware and software documentation in Adobe Acrobat format. The Teleport was maddeningly inconsistent when it came to performance scores, however. It could drop from a high of 54.7Kbps to 19.2Kbps during a connection and frequently slowed to under 40Kbps for more than 60 percent of a session. The fluctuations showed on longer downloads, with the device turning in the slowest average download time for our 1.5MB file tests. However, the modem performed especially well on impaired lines, dropping just 5 percent of connections. On ideal lines, it dropped 3 percent of connections, for an average drop rate of 4 percent. U.S. Robotics Sportster 56K Seven status lights and a power switch grace the front of U.S. Robotics' Sportster 56K Faxmodem. The power connector and RJ-11 line and phone jacks accompany the unit's dip switches on the back. An explanation of the dip switches and status lights is conveniently printed on the bottom of the unit. There's more software than you'll probably use on the included CD-ROM. Among the 30 products are 10 online service provider kits (including those for America Online, CompuServe and Prodigy), VocalTec's Internet Phone, the PointCast Network, Juno's free Internet e-mail service, SmithMicro Software's HotFax and U.S. Robotics' RapidComm data communications software. The Sportster's performance was less varied in overall transmission speed than our other x2 test subjects. It yielded the best average score for dropped connections (only 2.5 percent), and came in second in overall download times. Getting connected There are too many "ifs" where 56K is concerned, so we can't add any of these modems to the WinList at this time. That doesn't mean, however, that you shouldn't consider buying one, especially if your current modem operates at 14.4Kbps or less. Before you purchase any of these devices, however, be sure you know which of the two standards your ISP supports and understand that you may pay a premium to use this service. No matter what modem you buy, you'll need to become well-acquainted with the manufacturer's Web site. Your new modem's drivers will need frequent updating as standards change and developers figure out how to get more performance out of these devices. (For more information about 56K technology, see Windows on the Web, July.) Because of its U.S. Robotics parentage, the Sportster is the safest x2 choice for future compatibility. If you normally have problems achieving your current modem's rated speed, you'll want to consider the models that offered better performance on impaired lines, the K56flex Motorola ModemSurfr and the x2 Global Village TelePort. If you're lucky enough to have a brand-new network of telephone lines (either your neighborhood is only a few years old or your lines have been upgraded), the Motorola is still the best choice for K56flex adherents.
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