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56K Modem Issues

 

Introduction
Introduction
56k modems Facts
56k connections


56k problems
1. Symptoms
2. Things to consider
3. Solving problem

Modem Command Set

56K Driver List

Introduction

56K modems are the new wave of modem technology and they foster the hope of higher speed connections and an easier internet experience. While the technology is sound, and many users of 56k modems can and do achieve better connectivity, many others run into a variety of problems, either over time or right from the start. The intent of this document is to outline some of the problems that can occur when using a 56k modem, and to look at some of the solutions.


Facts about 56k modems

  •  FCC regulations mandate that the maximum speed allowed by these modems is actually 53k.
  • This theoretical limit of 53k is download speed only. Your modem can receive data at speeds of up to 53k. The fastest it will be able to upload (send) data is 33.6k.
  • Different 56k modems use different protocols to connect- V.90, K56flex, X2. These varying types can produce varying results and, though the v.90 standard is the newest and is widely considered the most robust, no one type is definitively superior to the others. Too much depends on your local conditions, what type of modem you are connecting to, etc.
  •  Modems started reaching their limit of reliability for data transfer over phone lines around 33.6k. A 56k connection asks a great deal of normal phone lines- more than phone companies are willing to try to provide support for. This is not dereliction on the part of the phone company; they are in the voice communications business. They are only obligated to provide data connections at 9600 baud.
  • Sadly, a certain percentage of internet users will not be able to get a 56k connection at all. Why this is so will be discussed in the next section.

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56K connections

Your modem's ability to achieve higher connect speeds is dependent on certain conditions- the release date of it's firmware and drivers, the condition of your phone lines and the distance to the telephone company exchange, the number of switches from analog to digital in the local loop. Problems in any of these areas can result in poor or unpredictable performance, difficulty connecting, or frequent disconnects.

1. Firmware and drivers:

    A modem has program code of it's own, called firmware. This is where much of the modem's identity resides. The protocols - that which makes a modem a 56k modem, or a 33.6k modem or whatever- are part of the firmware. Modem manufacturers are continually improving and updating firmware, and it is always best to ensure that one has the most recent releases. Even if your modem is 'brand new" there is no guarantee that the firmware is the most recent revision; a freshly bought modem may still have been sitting on a shelf for several months. Over time, a modem with old firmware may get "left behind" as Sonic updates the firmware of it's modems. A common complaint comes from people who used to be happy with their modem's performance until it began to degrade rather alarmingly over time. This is usually indicative of a firmware issue. Firmware updates are typically available for free from the modem manufacturer and installation is uncomplicated.
Drivers: It is worth it to find out about updated drivers for your modem when checking for firmware updates. The driver is a piece of software that the computer uses to communicate with the modem. Manufacturers make improvements to drivers from time to time and having both the right firmware and the right driver reduces the likelihood of error.

2. Condition of phone lines and distance to the phone company:

    Transfer of data using the techniques needed to support a 56k connection requires antiseptically clean phone lines. By "clean" we mean free of line noise or "static." Static, unfortunately, can sound a lot like the noises that a modem makes so it should be easy to see why it might interfere- all that erroneous noise can introduce so many errors in the data stream that a connection can be very hard to maintain. Phone lines all over are in varying states of repair and, like everything else in this world, they do age and decay. This can introduce line noise over time. Hisses, pops and crackles get introduced into the connection and data gets lost in the background noise.
Opportunities for degradation of the phone signal increase with the distance between you and the phone company. Some resources suggest that the only way to be absolutely sure of a reliable 56k connection is to be less than 18,000 feet from the phone company! That is just under three and one half miles. This is probably pessimistic but it does serve to underscore one point: if you live way out of town, miles away from the nearest telco exchange, your chances of having a perfectly clean connection will tend to degrade. If there is enough noise in the system, it can become impossible to make a 56k connection and sadly in these cases about the only way to get higher speeds is to move (or to convince the phone company to deploy brand new lines and equipment...)

3. Analog-to-digital switches in the local loop:

The local loop is the path from your modem to the telco and back again. Getting a signal to and from your modem will typically involve some switching on the part of the phone company; they have a lot of traffic to move and so they dynamically assign and reassign circuits to different people at different times. In the process, your signal might be converted to or from analog to digital and back again. The phone company also sometimes conserves copper wire by digitally multiplexing calls together, separating them at a junction box in your neighborhood, converting them to analog again and routing them to you. This is called a "line concentrator" or "pair-gain" circuit. While a full discussion of the mechanics of analog-to-digital conversion lies outside the scope of this article, let it suffice to say that the  process is inherently damaging to the signal. In a normal voice-to-voice conversation this is unnoticeable. However, a data connection under 56k protocols can not be achieved if the signal is subjected to more than one conversion. As  phone companies are continually having to find new ways to route an increasing volume of call traffic, multiple digital-to-analog conversions are becoming more common.

Other issues- Negotiation

Ideally, a 56k modem operating under any protocol should be able to attempt to connect at the highest possible speeds, negotiating down to slower speeds as much as is necessary to achieve a stable connection. In actuality many 56k modems are not good at reverting to slower protocols; they insist upon trying to transfer data with their higher rates, even if they have to do it slowly. This is roughly analogous to shouting very loudly and slowly across a crowded noisy room, rather than simply walking over to the person you are trying to communicate with and talking to them normally.

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Procedures for diagnosing a 56k problem

Step 1 - Symptoms

As previously stated, connection problems caused by 56k issues tend to manifest in one or more of the following ways. Look through this list to see if your problem is described.

  • Difficulty getting connected
    As negotiating a modem connection is a complex process, one should not expect to get online the first time every time. "Difficulty getting connected" in this case means that it is a struggle to get connected at all. If you only get a connection about half the times that you try, or worse, and if you get error messages along the lines of "can't establish a compatible set of network protocols" or "the computer you dialed is not responding," a 56k problem might be indicated.
     
  • Difficulty staying connected
    Bear in mind that if your connection is idle for fifteen minutes, you may be   automatically disconnected. By idle we mean that there is no traffic back and forth- no browsing to web pages, no downloading or uploading, no mail being sent or checked for. Please remember also that, given the vagaries of the internet, you might get cut off once in a while for no apparent reason and that the occasional disconnect is not indicative of a problem. A 56k problem might be indicated if you don't seem to be able to stay connected for more than a few minutes no matter what you do, or if it seems like you often get cut off at random intervals.
     
  • Slow connection speeds
    If you use a 56k modem and do not seem to be able to achieve speeds above 33.6 kbps, then the modem is probably not able to achieve higher speeds for one or more of the reasons discussed earlier and is falling back to the slower, more stable v.34 standard. If you are able to get connections that are reliable and stable but slower than you would like, the situation may- or may not- be improved by a firmware upgrade. If your connections are 33.6 or lower and you are experiencing any other problems listed here, then a 56k problem may be indicated.
     
  • Connections that seem slow, even though your computer says you are connected at high speeds
    Though your system may report that you are connected at a certain rate, the actual speed at which you are transferring data fluctuates. If your system reports that you are connecting at high speeds, and it seems slow, or if it seems to hang a lot while loading pages et al., then the modem may be having issues with data transfer under 56k protocols or with remaining at a consistently high transfer rate- both possible 56k problems.


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Step 2 - Things to consider

These problems can manifest suddenly with a previously satisfactory modem, or even with a brand new modem. Remember, "brand new" does not automatically mean "up to date" (see 'firmware and drivers.')  Here are some things to think about first, when approaching the problem.
 

  • Do you have current firmware and drivers?
    It is probably in your best interests to have the most recent firmware and drivers for your modem. Updates are typically made available for downloading on the manufacturer's website, which is all fine and good if you can get online. If you can not get a connection at all, do not despair- techniques for establishing a connection good enough to get you to the download site will be discussed later on.
     
  • How far from the phone company are you?
    If you live right in town and know that you are close to the telephone exchange, this is less likely to be a problem. If you live out of town, in the country, or on a mountain top then the likelihood that you will have problems getting and maintaining high speed connections increases dramatically.
       
  • Is your connection noisy?
    While disconnected, pick up the phone, press a single number to make the dial tone go away, and listen to the line that your computer is on. Does it sound clean and quiet? Or do you hear noises- hisses, hums, crackles and pops, clicking sounds? If you can hear any noises like that, the odds are good that they are enough to interfere with your data connection. Bear in mind also that even if you can not hear anything unusual, there may still be intermittent noise or interference that you can't hear but that your modem can. It is sometimes possible to get the phone company to check your phone line for noise.
  • Is anything else sharing the line with your modem?

    The best way to hook up a modem is to have it plugged directly into the phone jack, by itself, and to not have anything else plugged into the modem. Plugging a modem into a line splitter so that it can share the line with a phone, another computer, or a fax machine can induce static, line noise, and drops in line level.   The modem is also supposed to ignore devices plugged into it when it is online, but this does not always happen. Any of these things can cause problems.
     

      A note on fax machinesWhile the preceding statement holds true in general, a few computer users have also reported that their connection speeds and overall performance improved noticeably when they unplugged their fax machines, even if the fax machine was plugged into a different jack on the same phone line. We are not suggesting that you should permanently unhook your fax machine; however, unhooking it temporarily to see if it makes a difference to your internet connection is useful as a diagnostic approach.

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Step 3 - Solving the problem

Here are some basic steps to getting back online if you are having problems. Follow the steps in order or navigate by choosing one of the following links:

    1. It is a struggle to get online at all!
    2. I get connected, but it is slow or disconnects a lot.
    3. I am not sure if my phone line supports 56k.
    4. I would like to find a firmware upgrade.
    5. I want to disable 56k for my modem


1.  Making a stable connection.

This step is included to help you stabilize your connection, if you are having extreme difficulty. If, after following these instructions, you are able to make a solid connection, please return to this list again to see what can be done to improve your situation.

  • If you have not done so already, restart your computer. If you have an external modem, turn it off and on again.
    This is always a good first step. Computers and modems can, under certain circumstances, lose track of themselves and each other in such a way as to produce strange results. Restarting everything helps ensure that everything is initialized properly and functioning correctly.
  •  
  • Verify that your modem and computer are hooked up to the phone correctly. Temporarily unplug any fax machines et al., and plug the modem directly into the phone jack. If there is a telephone, answering machine, etc., plugged into the back of the modem, temporarily unplug it from the modem.
    Though checking to make sure you are plugged in correctly may seem silly, it is still worth doing (as a surprising number of internet service interruptions are caused by accident- house pets playing with the cables, accidental damage to the phone cable, etc.) See the previous section for an explanation of why you should try disconnecting your fax machine and other devices.
     
  •  Verify that your username, password, and connection settings are correct.
    Dial-up settings for any operating system can get corrupted, or entered incorrectly. It can still be possible to get connected with the wrong settings, but the odds are good that you will have performance problems. Make a New dial-up connection using the Internet Connection Wizard.


After working through these three steps, try connecting again. If you are now able to get connected, go to step 2. If not, then try the following:

2.     The Connection is slow or you often get disconnected.

If you are having a hard time making a connection, or if you are able to get connected, but typically at 33.6 or slower, or if you seem to get dropped at random, a simple number switch might help, for two reasons:
1. Different numbers take different routes through the phone system, and not all routes are equal when it comes to modem connections.
2. The quality of a modem's performance can vary a great deal depending on what kind of modem it is dialed into. Sonic.net employs various types  of modems on our end in order to ensure good connections with a wide variety of modem brands, and you may get better results by dialing into a different modem pool.



3.    Does your phone line support a 56k connection?

As discussed earlier, not all users can achieve higher speed connections (see Anatomy of a 56k connection.) Here are some ways to determine whether your line can support 56k.
 

  • Use the 3Com line test.
    3Com offers a line checking service that can be used by anyone with any 33.6 or faster modem. Instructions can be found at their website, here. Please note that performing this test necessitates the use of a terminal program, and that you will be making a few brief long distance calls. As this tool is 3Com's and not Sonic's, we can not offer any specific support for it.
     
  • Check your phone line for any obvious problems.
    Pick up the phone, press a single number to make the dial tone go away, and listen to the line that your computer is on. Does it sound clean and quiet? Or do you hear noises- hisses, hums, crackles and pops, clicking sounds? If you do, unhook any fax machines, answering machines, etc., that are sharing the line with your computer and then listen again. Any noise that you hear might be interfering with your modem's connection. Fixing this particular type of problem can be as simple as making sure the line is properly plugged in, to replacing the phone cable, etc. Or it can be as complicated as getting the phone company out to do repair work.
     
  • Contact the service department of your telephone company.
    You should be able to get some useful information from the telephone company. Ask them if you are on a pair-gain circuit or any other type of line concentrator. If they say yes, then your chances of connecting under 56k protocols are essentially gone. If this is true for you and you are having a hard time getting a stable connection, then your modem may be having difficulty slowing down and you should proceed to step 4 to find a firmware upgrade that may improve your modem's abilities to negotiate slower speeds or step 5 to disable 56k entirely.
    You can also get the phone company to check your line for noise. While they will probably be unwilling to say with certainty that you can have a 56k connection they should be able to inform you of excessive noise and spot any problems on their end that need repair.

If your phone line does not support 56k or if you are still having problems, please proceed to step 4.



4.    Finding a firmware upgrade.

A firmware upgrade can improve the speed and quality of a 56k modem on a line that is 56k capable. An upgrade can also improve some modem's ability to throttle down to the v.34 protocol if your line does not support 56k and your modem is having a hard time slowing down. Updates to your modem's firmware and drivers typically come from your modem manufacturer. Some computer manufacturers (e.g., Compaq, Hewlett-Packard, Apple) Provide updates as well. These updates are available for download, in most instances for free.
 

  • If you are able to make a connection: contact your manufacturer online
    For a list of many popular modem and computer company websites, go to our update page.

    Actual procedures for installing the new firmware and drivers vary from manufacturer to manufacturer, so follow their instructions carefully. As this is a hardware matter and the installation methods vary for different modems and different computer platforms, the only support that Sonic can offer is what you are reading here. For further technical support concerning upgrades, please contact your modem or computer manufacturer.
     

  • If you are unable to get connected reliably
    Go to step 5 and follow the instructions to disable 56k temporarily, and then go to our update page to find firmware for your modem.
  • iMac and Powerbook Series G3 users
    Apple has made an upgrade available that will improve the overall connectivity of the modems included in these machines. The upgrade includes improvements to the 56k component of the modem and also a modem script that will force the modem to connect under the v.34 protocol if necessary. Download this upgrade, recommended by Apple, from the Apple website.

If you are still not getting good performance and would like to disable 56k, please go to step 5.



5.    Disabling 56k for your modem

Sometimes disabling 56k, or forcing the modem to only use certain protocols, is the only way to get back online. You may need to do this for one of two reasons:

1. You are having such a hard time getting and staying online that you have no way of trying to check for an upgrade or test your lines, etc.
If this is true for you then disabling a 56k protocol- or disabling 56k entirely- may be the only way to go while you are trying to find a better resolution to the problem. Follow the directions below and then return to step 2 to continue looking for a better solution.

2. You have been able to prove to your own satisfaction that your line will not support a 56k connection and your modem is not performing well as is.
In this case, disabling the 56k capabilities of your modem may help. As stated previously, while modems are supposed to try to connect at the highest speed possible and then throttle down as much as necessary, some modems are in fact not very good at it. In many cases, a modem that does not perform well when it can not make a 56k connection will actually achieve higher speeds once 56k has been disabled.

Disabling 56k typically involves the use of an init string (short for 'initialization string.') an init string is a command sent to the modem that tells it how to behave during a dialup session. Init strings vary according to modem type and their implementation varies according to what kind of computer you have.
 

  • A quick trick to try first:
    Some modems can be tricked into not making a 56k connection with this simple technique. Go to your dial-up program and add 3 commas to the end of the phone number that you use to dial into Sonic. Do not put any spaces after the number! Just add 3 commas at  the end.

    Why this can work: adding commas to the end of the phone number instructs the modem to wait for an interval before proceeding. When you first make a connection with Sonic, our modems will try briefly to start a connection with 56k protocols, and if your modem does not answer right away, ours will stop trying and switch to slower protocols. Adding the commas should make your modem wait  to begin communicating until after Sonic's modems have stopped trying to make a high speed connection, and therefore both sides of the connection will be forced to try to connect at the lower, more stable speeds.

    Unfortunately, this trick does not work with every modem. If doing this does not help then remove the commas and proceed to the next step.
     

  • Determine your modem make and model
    For external modems, this is pretty uncomplicated- just read the case. for internal modems you will need to look a little deeper.
    Windows 95, 98: Click on the Start button, scroll up to 'Settings,' and select 'Control Panel.' Double-click on the 'Modems' icon. Your modem type and model should be listed here.
    Mac users:
    For Mac OS 7.6 and above:  go to your 'Apple menu,' Then to 'control panels,' and chose the 'Modem' control panel. your modem type will be listed here.
    For Mac OS earlier than 7.6: The designers of the earlier Macintosh OS did not provide a modem control panel. If you have a 56k modem installed in one of these machines, then software will have been installed with it that controls the modem and you should look there for specifics.
     
     
  • Find the correct init string
    Note: Different modems use computer chips from different manufacturers, and it is actually the computer chip (referred to as the chipset) that determines what init string you need. The list that follows is broken down first by chipset and then by manufacturer.

    First, consult the manuals and documentation for your modem if you have them. You may be able to find an init string that will do what you need. Even if you do not find a ready-made init string, you may be able to find what chipset the modem uses.

    Consult the following list to find your modem manufacturer and the recommended init string This is not a comprehensive list! There are many modems out there and this list covers a fair sample, but you may need to do some research on your own if you do not see your modem represented here, either on the internet or by contacting your modem or computer manufacturer.
     

  • If your modem supports more than one 56K protocol, you may want to try telling it which protocol (V.90, x2, or K56flex) it should use.
    Sometimes one protocol will work for you but others will not. Almost every line Sonic has supports all types of connections, but you still may want to choose which one you want to try. The list that follows will include strings to enable/disable on or more protocols wherever possible. If you wish to experiment, feel free- if you just want to disable 56k, use the string that disables all 56k protocols.


    Rockwell chipset:
    Global Village
    Hayes
    Bestdata
    Zoom
    Digicom
    Diamond/Supra
    Maxtech
    TDK
    Viking
    Xircom
    Boca

    For V.90 only, K56flex and v.34 disabled:
    AT+MS=12,1,34667,56000

    For K56flex only, V.90 and V.34 disabled:
    AT+MS=56,1,34000,56000

    Disable any and all 56k, use V.34 only (28.8/33.6):
    AT+MS=11,1
    If that does not work, try:
    AT+MS=11,1,300,33600
     


For Rockwell HCF chips (used in PCI cards):

To force your modem to try V.90 first, then switch to K56Flex:
AT+MS=V90

To force your modem to try K56Flex first, then switch to v.90:
AT+MS=K56FLEX

Disable any and all 56k, use V.34 only (28.8/33.6):
AT+MS=V34




USR Chipset (U.S. Robotics)
For Sportster (includes Telepath, Megahertz pc cards):
If you have a USR modem but are not sure what specific kind it is, try the Sportster string first.
X2 is a protocol used mostly by USR modems. There are other brands that use X2; typically they use the same commands as USR Sportster modems.

For X2 only:
ATS32=66

For V.90 only:
ATS32=34

Disable any and all 56k, use V.34 only (28.8/33.6):
ATS32=98

For Courier:

For X2 only:
ATS58=32

For V.90 only:
ATS58=1

Disable any and all 56k, use V.34 only (28.8/33.6):
ATS58=33

To make either Sportster or Courier enable both protocols:
AT&f1
(This string simply causes the modem to load it's factory presets every time it is used.)


Lucent chipset: LT Winmodems

Lucent makes the K56flex LT Winmodems shipped in Compaq, IBM, HewlettPackard, Sony, and other computers.
Their chips are also used in modems from CPI/ViVa and others.
 

To disable 56k For Lucent-based modems that are K56Flex only:
ATS38=0

For Lucent-based modems that support both K56Flex and V.90:

For V.90 only:
ATS38=0-V90=1

For K56Flex only:
AT-V90=0S38=1

Disable any and all 56k, use V.34 only (28.8/33.6):
ATS38=0-V90=0



  • If you don't see your modem listed here:
    You may need to hit the net or call your computer manufacturer if you do not see your modem here or if it is not readily apparent exactly what kind of modem you have.
  • Where to put the init string

First, a word about init string use: Use of the wrong init string usually causes error messages, and some of them can be alarming ("There is no modem," "Modem not responding," etc.) If you see an error like this after you've applied the string, don't worry- just remove the string, restart the computer, and look for a different string.

Init strings use a specific grammar: It must begin with 'at,' there must be no spaces, and the string must be either all lowercase or all uppercase. Failure to observe these rules will result in failure of the string, so be attentive; copy these strings down exactly as they appear.
 

Windows 95, 98, NT
go to Start button > Settings > Control panel > Modems > Properties > connection > advanced. Place the string in the Extra Settings field. (Click here to see screenshots of this procedure.)
Don't mix cases; either use all lower-case or all upper-case letters. If there is nothing else already in this field, enter the whole string. If the you have an init string already, You can try putting this at the end of it, but make sure you drop the AT from the beginning of the string!

    Macintosh
    iMac and Powerbook Series G3 users
    Apple has made an upgrade available that will improve the overall connectivity of the modems included in these machines. The upgrade includes improvements to the 56k component of the modem and also a modem script that will force the modem to connect under the v.34 protocol if necessary. Download this upgrade, recommended by Apple, from the Apple website.
    If you still wish to disable 56k after you have installed the upgrade:
    Go to the Modem control panel. It should be displaying either "iMac internal 56k" or "G3 internal 56k," depending on which type of computer you have... click on the selection bar and choose "iMac internal 56k (v.34 only)" or "G3 internal 56k (v.34 only).
    If you use  Configppp, Freeppp, Open Transport:
    Consult these screenshots for placement of the init string. Don't mix cases; either use all lower-case or all upper-case letters. If there is nothing else already in this field, enter the whole string. If the you have an init string already, You can try putting this at the end of it, but make sure you drop the AT from the beginning of the string!


We hope that this resource has been helpful. Owning a 56k modem can be a bit like owning a fancy sportscar: you should be able to get great performance out of it but it may sometimes involve tinkering to get it to work right. Good luck!


Would you like more information?
If you would like to read more about managing a 56k modem, please check out these great sites:

56k=v.Unreliable
56k Modem Central

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