If you are having repeated pattern of disconnects then here are some suggestions..... With modems the most common cause of disconnects is connecting at TOO FAST a speed, causing frequent modem retrains, which in turn cause frequent disconnects. Most telephone lines will not support the maximum speed of the modem. With V.34 modems the best you should expect is 24,400 and any time you get a higher speed connection expect more frequent disconnects. With V.90 56Kbps modems, the expectations are highly dependent upon how the telephone company has provisioned your service and expectations range from a low of V.34 speeds to around 48Kbps. EagleNet's local loop to the telco CO is very high quality so the modems will be fooled into training to a speed that your local loop from your house to your CO will not support for very long unless you are very close in cable feet to the CO. Speed renegotiation is some the most problematic code in modems and you can not rely upon it to hold a connection, in many cases it will fail and you will be disconnected. Try dropping your connect speed by forcing a lower speed, if that stops the disconnect then line noise may be the problem. The second most common cause of disconnects is modem incompatibilities, again typically related to re-trains. Get the latest firmware revision for your modem. Don't assume because you bought your modem recently it has current firmware. The statement 'my modem has no problems with xyz provider/service/modem etc.' is not particularly meaningful. Every modem will be compatible with someone, but we have yet to see the modem that is compatible with everyone. Our systems have been very reliable with current versions of firmware on modems from Hayes, Zoom, Supra, Motorola and many others... the biggest headaches come from the very low cost units. As modems become faster they also become more complex. Some modems have a way to record the reason why a connection failed. Popular methods include the ATi2 or AT&V1 command (these are modem specific, your modem may vary). If you can, try using an external version of another brand modem and see if the problems disappear. Another common cause of disconnects and poor line speed is line noise. Unplug EVERYTHING connected to your phone lines: caller ID boxes, extension telephones, cordless telephones, other modems, fax machines. Also unplug your laser printer from the AC wall outlet. We have learned that many telephone line 'surge protectors' or 'noise filters' will seriously impair your phone line. The modem should be the ONLY thing connected to your phone lines... if the problem goes away... then you have something in your house causing you to disconnect. Do not route the phone line within three inches of any electrical cord or extension cord, or PC CPU cable, Printer cable, Monitor cable, any electrical appliance or power supply. Especially avoid laser printers, cordless telephones and uninterruptible power supplies (UPS's). Inductance from electrical lines and radio transmitters wreaks havoc with phone lines. If the line noise is not being induced inside your house it may be induced in the cable somewhere between your house and your local telephone exchange central office. Your line may have a one or more of conditions the telco calls 'bridge', 'ground loop', 'cross talk', or 'bad loading coil'. Any of these conditions will cause random noise and unpredictable disconnects. For noisy lines, try increasing a setting that tells the modem how long to wait (in tenths of a second) before hanging up when it loses carrier detect. This guard time allows the modem to distinguish between a line hit, or other disturbance that momentarily breaks the connection, from a true disconnect by the remote modem. For example: S10=100 setting will make your modem wait 10 seconds to make sure the other modem is really gone before hanging up. If this seems to help, contact your phone company and request the line be checked for noise at the network demarcation block at your house. Sometimes defective cables and loose connections will cause disconnects. For external modems, if the serial cable is old, adapter pins bent, or cable cracked, replace it or try another one. Make sure your serial connections are TIGHT. Examine your telephone cable between the wall jack and the modem, or better still try replacing it. If portions of the telephone cable between the network interface and your wall jack have been stapled to the wall, examine the cable carefully. If possible try another jack, or the jack on the telco network interface itself. If you have call waiting, remember to add a *70, to the front of the Integrity Online phone number to disable call waiting. Otherwise every time someone calls you, the modem will disconnect. You may have a hardware conflict. Frequently we have seen internal modem cards configured inconflict with another COM port which will seem to work OK for a few minutes of the connection and then just 'freeze up'. Check to see that your motherboard com2 port does not conflict with your modem, see your modem documentation for instructions on detecting and correcting IRQ conflicts. For a very detailed discussion of this issue, see our FAQ titles "What COM port should I use with my modem?". Also, if you have an Ethernet Card in your PC and an internal modem, it is almost certainly causing some problems with high-speed modem connections over 9600 baud. The only cure we have found is to remove the Ethernet card or use an external modem on an high-speed serial port. Although rare, your modem may be set up to automatically disconnect after a certain period of inactivity. You may be able to fix the carrier loss problem by adding these settings to your modem initialization string: S19=0 This disables the inactivity timeout on most modems. If you want your modem to timeout and hangup after a certain amount of time, you can replace the 0 with the number of minutes you want it to timeout after (up to 255 minutes.) Generally, you should hold a connection for as long as you wish.... there will ALWAYS be an occasional disconnect, we are after all dealing with phone lines pushed to the very limits of their capacity when using the latest generation of modems. But you should not get repeated disconnects, if you do something is wrong and you should methodically follow the steps above.
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