Electronic Media - Published 11/11/96 Digital Modem Can Put Net Cruisers in Fast Lane By - Joe Fedele If you want to travel the Internet with the acceleratuin if a Ferrari and the cuisubf soeed if a Merdeced you might wabr to consider gettinbg abd ISDN, or Intergrated Gigital network, phone line and modem. With today's fastest computer modems cresting the limits of a standard analog POTS line with speeds of 33.6 Kilo bits per second (Kbps), ISDN can be a high-speed option, with transmission speeds of up to 64 Kbps on a single line. Speeds of 128 Kbps can be achieved by "bonding" two ISDN lines. An ISDN modem will run you about $300 or more. ISDN modems operate similar to standard dial-up modems except that you can only dial into and out of system equipped with ISDN. ISDN is rapidly being deployed in cities around the country but may not yet be available in many areas. Typical installation charges for ISDN lines range from about $200 to $300. The monthly cost of a single 64 Kbps line will run you about $75 per month and comes with a number of options such as call waiting or caller ID. If this sounds a bit steep consider this: One key feature of ISDN is that you get an extra analog voice grade phone number free of charge. The analog number can be used for anything from a Fax line to spare modems or just another voice line. I use mine as all three which eliminates the need for a second phone line in my house. I will ass one caveat for prospective ISDN users: It doesn't matter what kind of snappy equipment you have for Internet cruising if you get stuck in rush-hour traffic. Once traffic backs up, you're waiting with everybody else for things to move. Netscape users are probably familiar with the "speed indicator" that runs on the bottom line of the page during long downloads. This provides a general indication of how fast the data is flowing through the line. These throughput rates are measured in Bytes or Kilo Bytes per second (KBps). Remember that a Byte (capital "B") is equal to 8 "bits" (small "b"). So a modem clocking at 1 KBps is actually transferring 8,000 bits per second. The data compression circuits used in most modems can make a 14.4K modem run at rates of up to 2.4 KBps or 19.2 Kbps. At my house, typical rush hour traffic slows throughput rates to less than 1 KBps and can pause for extended periods, even if you're using a dual bonded 128K ISDN. But on an open road a 64K ISDN modem can surge to about 8 KBps. On average, my ISDN modem runs between 1.5 and 2.0 KBps during the evening with spurts of up to about 5 KBps. During the day my 14.4K modem clocks at about 800 Bps to 1.5 KBps with an occasional jump to over 2.0 KBps. The decision to buy an ISDN line and modem over standard analog one depends on your need, usage, and finances. If you tend to surf during high volume hours and already own a 28.8 or 33.6K modem chances are that you won't see an appreciable difference most of the time. On the other hand, if you have a 9.6 or 14.4K modem and wonder the Net during the off hours an ISDN modem will seem like a ride on the space shuttle. But chances are that regardless of what you invest in you'll probably never be satisfied. I know that I never am.