CVC Internet Help Guide

Connection FAQ

Q: I have a 28.8k - 56k modem, but I can't connect at the highest rated speed. Why?

Your modem will connect to us at the highest possible speed based on your phone line conditions.
Certain modems have a better track record connecting at higher speeds than others. Generally, brand name
(USR, Supra, Hayes, Zoom, etc) modems provide better connections than OEM or generic-brand modems.

Below is a very informative explanation from USRobotics on this topic.
Very few people can get a consistent 28,800 (V.34 modem) or 33,600 (33.6k modem) bps connection.
Speeds of 28,800 bps or faster, require pristine line quality along the entire length of the connection.
However, V.FC, V.34, and 33.6k modems are capable of pushing the limits of analog phone lines,
commonly offering connect speeds of 21600, 24000, and even 26400bps or higher.

Variations in line quality are typically the culprit for low connection rates.
Everyone occasionally gets “a bad line” and has to hang up and call again to get a better
connection. However, if you find that you never or rarely connect at rates above 19200 bps,
you will want to investigate the line quality of your connections. Begin with the following:

Try calling a different location.
Line quality differs from region to region and it may be a problem with the lines or modem
at the other end of a particular call. Try connecting with a local call. Sometimes the connections
within a long distance call can cause impairments (if this isolates the problem, you can try switching
long distance companies or request that they try to fix the problem). Try plugging the modem into a
different phone line or wall jack. If you know someone else in your area with a high speed modem,
ask what type of connections they make. Try making the connection from their location.

If you encounter the same low connection rates, the problem may be resulting from impairments
along the lines running to the local telephone company or within your home or office.

Your telephone company or a private consultant may be able to help.

Software Setup and Modem Configuration
In addition to line impairments, modem configuration and software
setup can affect connection rates and throughput.

Dropped Connections
Dropped connections can occur when there is a sharp decrease in line quality during a call.
V.34 modems will switch to rates as low as 4800 bps to compensate for these changes.
If the loss of quality is extremely severe, they will drop the connection.

Dropped V.FC Connections
V.FC connections can only switch rates down to 14,400 bps. If you connect using V.FC and
line quality drops below that allowable for a 14,400 connection, the modem will disconnect.
If this occurs frequently for a particular call, you will want to disable V.FC before calling that
modem again. A different modulation protocol (v.32bis, for example) will be established and
will allow the modems to switch to lower bit rates as line quality warrants. If you want to
disable V.FC, and your modem has S-Registers in the thirties, send the modem ATS32.1=1.
If your modem has S-Registers that go into the fifties, send the modem ATS56.7=1.

Remember to return the modem to its original configuration after the
call is completed by resetting the modem or entering ATS32=2 or
ATS56=0 depending on the model you have as stated above.

Some V.FC modems make by other manufacturers do not support rate switching.
These connections are more likely to drop. For these calls, you can force a lower connect
speed by locking the modem to a lower link rate via the &N command, or disable
V.FC by entering ATS32.1=1 or ATS56=128. Remember to reset the modem or return
it to its original configuration after the call is completed (AT&N0 or ATS32=2/ATS56=0).



Q: HELP! I get disconnected while actively using the Internet?
What could the problem be?



1. Make sure your idle timer is turned off.
Win95 users go to Control Panel, Internet. Click on the Connection Tab.
Uncheck the Idle Timer if it is checked.

2. Make sure you do not have call-waiting on the phone line your modem uses.
If you do, turn it off when dialing the Internet.

3. Poor line conditions cause the vast majority of unexpected disconnects.
If you can hear any noise on your line, then its very likely you will not be able to connect
reliably. If you suspect line noise, give your phone company a call and ask to have your
line checked for noise. Some telcos provide a data-quality line for modem use.

4. In rare cases, modem incompatibility can cause random disconnects.
We've seen this with some older generic modems.

5. Replace the phone line from the back of your modem to the wall.
Some low grade cable can cause problems.

6. Try calling from a different location.
This is an easy way to see if it is your phone line
conditions that are causing the disconnects.


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