With over 25 years of experience in providing data communications products and services to businesses and residents, NetDotCom has had the opportunity to work with modems from many manufacturers.
Unfortunately, not all modems are of equal quality.
There are three main types of modem designs: SOFT, Controllerless, or Hardware
A modem is a hardware device attached to a computer which allows the computer to communicate with another modem over a telephone line. A modem does for computers what a telephone does for humans. Just as a telephone allows two
humans to speak to one another over telephone wires, a modem allows two computers to speak to each other over telephone wires.
Modem Components - All modems, regardless of whether they are of the internal, external, include three key components in order to function:
- Interface Circuitry: Connects the modem and pc to the telephone line.
- Digital Signal Processor or Data pump: Converts analog (sounds) to digital (1 & 0's) and vice-versa.
- Controller: Carries out commands sent to the modem (dial, hang up), performs error correction, data compression and handles data flow between the computer and DSP.
Hardware vs. Windows vs. Software Modems
Controller or Hardware Based Modems: We recommend USR Performance Pro Modem
This type of modem design is usually the most reliable, highest performing and most costly. These modem designs are called hardware modems due to the fact that they have all three basic components of a modem. Including
memory to hold the firmware (program code) that the controller uses to operate the modem. The host computer simply sends the commands and data to the modem and lets the modem transmit the data over the phone line. The onboard modem controller
makes sure the data gets to and from the Internet reliably and error free.
Win Modems: We recommend Lucent or Agere based modems
Win modems are modems with a DSP but no hardware controller. The control functions of the modem are now performed by the CPU in your computer. Problems with this design can arise when the host computer doesn't
have enough computing resources (CPU Speed & RAM memory) to perform all of its tasks efficiently. Like running several programs at the same time. Another issue is program errors that cause programs to crash (Illegal Operation
errors). If one of these program crashes causes the modem controller program to malfunction your modem will operate erratically or not at all until you reboot the PC which reloads the modem controller program from the hard drive.
Because the added expense of the controller and associated memory have been eliminated these modem usually cost less than controller based modems
Soft Modems: Not Recommended
Are modems without a DSP or hardware controller. Software based modems offload all of the communication processes to software that runs on your computers' CPU/memory, thereby reducing the overall speed of your computer. The worst
designs offload everything, reducing the modem to nothing more then a connector.
If you have a older, less powerful computer and there are other programs running, including background programs that do not appear as a visible window on the screen, the software program that does the modem's work can be starved of CPU
time. When this happens, the modem can not complete its required tasks in a timely manner, causing "timeouts" and disconnections. In addition, software modems typically have weaker error correction and flow control
capabilities, meaning they cannot handle noisy phone lines well. This can cause disconnects because of
the modem's inability to handle phone line noise.
Software modems are very common on Windows-based computers. Most are very inexpensive to manufacture and because of this they are generally included with nearly all new computers. However, some brands or models will not work correctly on
older versions of Windows. They generally require at least a 400 Mhz CPU with 96 Mb of RAM to operate reliably. Which makes them a very poor choice for older computers running Windows 95, 98 or ME
Since most (or all) of the modem's processes run in software that is loaded when Windows starts, any application crashes can have an adverse effect on the modem's reliability and performance. In
some instances a reboot is required to restore operation.
Some common software-based modems:
- Rockwell or Conexant HCF, HSF Soft 56k
- Motorola SM56
- Cirrus Logic/Ambient (MD-56)
- ESS Teledrive
- PCTel HSP-Micromodem or "audio/modem riser"
Here are some tips to tell software-based modems from hardware-based modems:
- Nearly all external modems (modems that sit in a separate box outside of the computer) are hardware-based modems. This kind of modem is ideal--it does not require you to take apart your
computer, although they do require some extra cabling. (EXCEPTION: External USB-based modems are usually software-based.)
- If the label on the modem says it requires "Windows" then it usually is a software modem.
- Most software modems will also indicate on the box that they require at least a Pentium-based computer; hardware modems will indicate that they will work on almost any computer regardless of the CPU's speed
- If the text on the modem box mentions "HSP", "HCF", "HSF" or "controllerless" it is definitely a software modem.
- Hardware modems almost always cost more than software modems. Most software based modems sell for less than $50.00.
If you are having trouble with a software modem, the ideal solution is to purchase a good, well-established, brand-name hardware-based modem, like the
US Robotics Performance Pro Modem NetDotCom sells online for $78.99
Finally, for optimum performance of any modem, you should always check with your modem manufacturer to see if there are any updated drivers/software or firmware available for the modem. These free
updates typically fix bugs in the earlier versions of the modem software and are the quickest way to improve your connection quality. Modem updates are also usually available at your computer
manufacturer's website as well as the third-party sites listed below. The one good thing about software modems is that they are easily upgradeable--and if you are having difficulties with them you should obtain these updates.
Click here for instructions on obtaining updated software, drivers or firmware for your modem.
Lots of additional information about the quality of particular 56k modems and detailed explanations on resolving problems with their use can be found at: