modem speeds revisited

Bill Woodland (wcw@bga.com)
Sat, 19 Jul 1997 12:45:26 -0500


There was some discussion on this list recently about modem connection
rates. I would like to clarify a few things.

There are two different rates invloved here. One is the DTE (Data Terminal
Equipment) speed, which is the speed that the COMPUTER talks to the MODEM.
The other speed is the DCE (Data Communications Equipment) speed, which is
the speed at which YOUR modem talks to your ISP's modem. Most newer modems
can talk to the computer at 57600 or even 115200, even tho their maximum
DCE speed may be limited to 28800. The modem does the "speed matching"
between the two connections; modem to modem and modem to computer. =20

DTE Speed:
In DUN, right click on your connection and choose Properties, then on
Configure. The "Maximum Speed" setting there tells Windows how fast it can
talk to the MODEM ITSELF. Of course, if you set this too low, you WILL be
limiting your connection speed, but if your modem can handle it, set this
to 115200. If you have errors at this speed, set it down to 57600.

DCE Speed:
Many modems report the DTE speed as a default. My Motorola Lifestyle 28.8
modem reports the DCE speed as a default. Here's what my modem book says
this about the \V command:

\V Computer to modem speed
\V1 Computer to modem speed with error correction and data compression
information
\V2 Modem to modem speed only
\V3 Modem to modem speed with error correction and data compression
information
*\V4 Modem to modem speed with modulation, error correction and data
compression information

* default

Since the \V4 is the default for my modem, I see the actual connection
speed to my provider. The command to do this may vary from modem to modem,
so check your modem manual. If the default is to report computer to modem
speed, then you're being misled about the amount of data you can=
send/receive.

If you have a 28.8 modem and your Win95 DialUp Networking (DUN) connection
always reports connection speeds of 56700 or similar, you need to find the
command for your particular modem that tells it to report the DCE (modem to
modem) speeds. Then go to DUN, right click on your connection, choose
Properties, then click on Configure/Connection/Advanced and in the "Extra
settings" edit box you can put that command in so that your actual modem to
modem speed will be reported.

Once you have done all this, you should be able to see the speed at which
your modem actually connects, and you can adjust your CU-SeeMe rates
accordingly.

Bill Woodland (Squeek =A9) PC questions only, please.
URL: http://cu-seeme.cornell.edu/~WCW
CU-SeeMe Unsubscribe? Details at http://cu-seeme.cornell.edu/listinfo.html