How do V.92 modem speeds compare to ISDN, ADSL and Cable speeds?

First, remember that V.92 is asymmetric in nature, the same as ADSL. It offers download speeds from the WEB which are higher than it's upload speeds. This means that it is inherently different from ISDN and has been optimized, like ADSL, for Internet access. In fact it is optimized primarily with V.44 compression rather than with purely higher transmission speed as found in ADSL and Cable.

Because of this it is not possibly to directly compare the different devices except in terms of the Internet experience itself, including Web browsing. Given optimum V.92/V.44 performance of approximately 300,000 bps, this still means that that it will operate at less than half the speed of most broadband services (which range from 600,00 bps to 1,500,000 bps).

Zoom also makes and markets ADSL and Cable modems to support broadband service; we feel that the V.92/V.44 modems will significantly improve the Internet for many users that do not have access to or wish to pay for broadband service but we do not represent them as competition for broadband. They will, however deliver equivalent or better Internet access than most ISDN devices as long as the application does not require equal speeds in both directions.