This question is probably asked by more people, to more Internet service providers, than any other question regarding Internet access. It is a natural assumption, especially by the novice on-line user, that if they have a 56K modem, they should be able to connect at 56K. Oh to live in such a perfect world!

In order to better explain some of the reasons why this just does not happen, the first thing we need to do is explore some background. The first step in this exploration is to look at a restriction that is placed upon analog telephone lines (the type of lines that almost all normal dialup customers use), and how it effects a modem connection. Because of the voltage restrictions that are placed on the normal analog telephone line by the government, the absolute maximum connection rate that a 56K modem can make is approximately 52.8K (usually referred to as 53K). So much for the "56K" connection you thought you were going to get right off the bat.

In other words, IF the phone line will handle it, and IF the modem is programmed to work at its absolute maximum potential, and IF a lot of other behind the scenes conditions are met, it IS possible to get 53K out of the 56K modem, but that is all. So why then when the customer dials up to their ISP can't he (or she) get 53K? To explain this, we again need to do some more exploring.

One of the prime reasons that a reliable connection cannot be made at a rate that is even close to the 53K maximum right now, is the newness of the modem code. This code is what makes the modem work. The V.90 modem code was established as a standard for these modems only just a little over a year ago. The code is for the most part all new, and is FAR from being perfected (much the same as the codes were for the 2,400 bps modems when they were first introduced, and again for the 9,600, 14,400 and 28,800).

What does this do for the modem, and its usage then? It just plain makes it "flaky" and not work correctly. It is subject to failed connections upon dialup. It is subject to connections at well below what it is rated at when it does connect. And it is subject to disconnection at the most inopportune times when traversing the Net. For this reason, almost all of the manufacturers of 56K modems have released countless revisions to their V.90 code since its beginning and, as in the past, will continue to release new code until these "bugs" can be worked out. While it is of course up to the Internet Services Provider to upgrade their modem code as it becomes available, it is also up to the consumer to see that their modem is upgraded also to take advantage of the improvements.

To compound the modem code issue, is also the issue of the "drivers" that the computer uses to properly tell the modem what to do and how to act (this is normally referred to in the computer world as "initializing"). In days gone by, modems had to be initialized manually by typing in complicated cryptic strings of gibberish each and every time the modem was used. In today's world of the Windows operating system the drivers do this initialization.

If the drivers initialize the modem incorrectly, or the wrong drivers are used, the modem either fails to respond at all, or it doesn't do what it should when you try to use it. So again, like the programming code in the modem that is new and far from being perfected, are the drivers that are ALSO new and still in their infant stage for the 56K modem. Luckily though, also like the modem code, manufacturers have been releasing new drivers for their modems since the 56K protocol was introduced. The new drivers attempt to tell the modem the correct things to do and how to act with varied telephone line conditions. There is no doubt that the modem manufacturers will continue to release new and improved modem code and drivers until they get it right. But again, it will continue to be the modem "user's" responsibility to keep their modem code and drivers updated if they wish to obtain anything close to peak performance.

So now we have explored the 56K modem itself, and the drivers that make it work as a potential problem. Lets once again go back to the telephone line it is hooked to, and some of the other limitations that are placed on the modem's ability to obtain the maximum speed.

Probably one of the prime reasons that less than maximum connections are obtained from the 56K modem (if the code and drivers have been updated), is the telephone line itself and its inability to handle enough frequencies to get the higher connection speed. While going into this area just cannot be done without getting somewhat technical in nature, we will try to keep it as simple as possible, but yet explain what a modem needs on a line in order to work. First, we need to keep in mind that in order to support your normal telephone conversation, and make your voice be heard and understandable on the other end, a frequency range of only 11 kHz is required. But, in order for a modem to work, the telephone line must be capable of handling a frequency range of AT LEAST DOUBLE of whatever connection speed you are going to get.

In order to understand this, let's look at some actual numbers. If you are going to get a connection speed of, say 53K (the maximum your 56K modem will do), your telephone line would have to be capable of handling a frequency range of AT LEAST 106 kHz. If you are going to get a connection speed of 45K, your telephone line must be capable of handling a frequency range of AT LEAST 90 kHz., and so on. No magic here, just plain simple math. But all of these frequency ranges are a FAR cry from the mere 11 kHz that it takes to support your voice conversation that the telephone line you are using was designed for.

Now as we all know, almost any telephone line WILL handle more than the 11 kHz that is required for voice. But how much more? Will your telephone line handle 20 kHz? Great, you can now probably make a 9,600 bps connection to your provider. Will your line handle a frequency range of 30 kHz? That is even better, because now you should be able to make at least a 14.4 connection. A phone line that will handle a range of 60 kHz will normally allow you to make a 28.8 connection and so on and so on. But at some point there is a limit, and when you hit that limit, your maximum connection speed will be limited also.

If there is a "hum" on the line, that will limit the frequency range the line will handle (the hum itself is using part of the frequency range). If there is any other type of noise on the line or cross talk, etc., that will also use part of the frequency range that is available. And sometimes there are things on a telephone line that just plain limit the frequency range it will handle, with no recognizable abnormalities at all. But for whatever reason, when we are all trying to use a phone line that is only "required" to handle a range of 11 kHz to do the job it was intended for, at some point we are going to bump up against whatever frequency range there is as we push it towards higher and higher connection speeds.

Lastly, when discussing why the full potential of your 56K modem cannot be achieved, we must realistically take a look at some of the things the telephone company does which makes it totally impossible to achieve even close to the upper limit of the 56K modem. In today's world of ever-expanding housing, the telephone customer's ever-expanding need for additional phone lines, and the ever-expanding need to keep costs down, the telephone company has devised a way of making at least two lines out of one.

In many areas, especially ones that are fast growing, the Telephone Company doesn't have enough copper lines to go around. So they either employ a neat little device called a "pair-gain device", or a "SLC" (pronounced "slick") is placed in the circuit, which in either case lets them run multiple phone lines across what WAS, one set of copper wires.

Again without getting too technical, lets quickly look back at the first paragraph of this article. Remember we talked about how the government has a limit on the voltage that can be put across a normal phone line that limits a modem connection to approximately 53K? Well, this voltage now with a pair-gain device, is divided by 2 (because it is now supporting "2" phone lines). All of a sudden what was a maximum connection of 53K (which is actually closer to 52.8K) now becomes a maximum connection of only 26,400. A severe limitation to the 56K modem, but a connection speed that is seen by far to many people in today's on-line world because of the use of pair-gain devices. In areas where a SLC is used to provide extra lines, many times another analog to digital conversion is made by the SLC which also kills the 56K protocol.

In summation, it can be seen that there are several reasons why your brand new computer, with its brand new 56K modem does not connect at 56K. There are limitations in the modem itself, there are limitations in the computer software that tell the modem what to do, and there are limitations in the telephone line that your modem is hooked to. But if modem technology goes as it has in the past, there IS hope. With past experience as a teacher, there is probably little doubt that in another year, or two, or three, when we are all trying to hook up with the new V.xxx protocol at a speed of 115,200 bps, we will then be able to make a full 56K protocol connection first time, every time, without a hitch. And wonder how we ever got along with a speed so slow.

Written for the Ludington Daily News
January, 2000 by Lyle A. Reene