The company said the maximum downstream transmission speed will be limited to 53 kbps, not the 56 kbps originally promised. Federal Communications Commission regulations "limit the signal level" that digitally connected server equipment can transmit, the firm said.
U.S. Robotics' x2 technology overcomes the speed limits of current 28.8-kbps modems based on the ISP having a direct connection to telephone companies' digital switches.
The company said today that tests showed that "the vast majority" of users would be able to use x2 technology, while its modems would automatically default to lower speeds if such connections weren't possible. The test results were based on over 20,000 calls in seven Bell operating company regions, the firm said.
U.S. Robotics says it is in beta testing of its products and expects to start shipping initial consumer products later this month.