How to Select a Dial-up Modem

Despite the much higher nominal speeds provided by broadband (e.g., DSL and cable), dial-up connections to the Internet are still widely used and offer some important advantages, including lower cost, more widespread availability and lower security risk.

Purchasing a dial-up modem can be a bit tricky, especially when used with computers that run Linux or other minority operating systems. In particular, it is easy to make the wrong decision and buy a unit that will not work at all with such systems. Below are a few things to keep in mind in order to obtain the most suitable modem.

(1) The first is to make certain that the modem is built to the latest standards, i.e., V.92. This ensures that it will not only have the fastest possible speed for a dial-up modem, i.e., 56Kbps (kilobits per second), but will also have certain other advanced features. Fortunately, virtually all new modems manufactured in the past several years conform to this standard. Caution should be exercised with regard to used modems, which might have been made before this standard came into being. Usually the standard to which the modem conforms is written on the modem itself and/or on the packaging or documentation that comes with it.

(2) A second thing is to attempt to confirm that the modem is actually compatible with the operating system(s) to be used in the computer. The main problem is that a large number of dial-up modem models are only compatible with the Microsoft Windows operating systems. These so-called win modems or soft modems replace some of the hardware used in generic modems with software that is included in the Microsoft Windows operating systems but which is difficult to duplicate on other operating systems.

The packages and documentation for new modems will typically clearly state that the modems are compatible with the Microsoft Windows operating systems. However, very often they will not state whether they are compatible with other operating systems1. Often the salespeople selling the modems do not know either. Thus, it is best to do some research on the Internet to find out if specific models are compatible with the intended operating system or not.

(3) A third consideration is whether the modem is internal or external. Each has its advantages and disadvantages. Internal modems are usually cheaper, and they consume less space because they are inserted into a slot on the motherboard (i.e., the main circuit board) inside of a computer instead of used outside of it. However, they require opening the computer, and this can pose a risk of damaging the computer by an inexperienced person.

Although they are typically significantly more expensive than internal modems and consume more space, external modems do not require opening the computer. All that is necessary is to make a simple connection to a serial port on the back of the computer via a cable that usually comes with the modem and also to connect it to a power supply.

External modems also have several other advantages. One is that they usually contain small displays or LEDs (light emitting diodes) that provide information about the progress of connections and related diagnostic information. Another is that they can easily be moved from computer to computer. Particularly important for users of Linux and other minority operating systems is the fact that many more models of external modems are compatible with such systems than are internal modems.

1There is some suspicion among users of Linux and other alternative operating systems that this is the result of pressure applied to the manufacturers of modems in attempt to help keep such operating systems from becoming more convenient and easier use.

Created December 16, 2005.
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