How to Change the Default Port Speed on a RAS Server

MORE INFORMATION

Windows NT RAS sets two bits per second (bps) speeds for each RAS serial port:

• The carrier bps speed.
• The connect bps speed also referred to as port speed.

The carrier bps speed is the speed is read from the MAXCARRIERBPS parameter in your modem's section of the %SystemRoot%\SYSTEM32\RAS\MODEM.INF file. The carrier bps set the speed at which the two connected modems send data over the telephone line.

The connect bps speed, or port speed, is the speed at which data is transferred between your modem and the serial port on your computer (also known as the Data Terminal Equipment [DTE] to Data Communication Equipment [DCE] bps transfer rate).

While the carrier bps used by the RAS server modem may be different for each RAS connection due to the connecting modem capabilities, line noise, etc., the RAS server connect bps is always initialized at the same speed. The connect bps speed used by the RAS server is read from the MAXCONNECTBPS parameter in your modem's section of the %SystemRoot%\SYSTEM32\RAS\MODEM.INF file when you install your modem. The speed is then stored in the INITIALBPS parameter of the SERIAL.INI file. The RAS server service then uses the INITIALBPS parameter in SERIAL.INI to initialize the port speed whenever the RAS server service is started.

To Change the Port Speed (bps):

NOTE: Verify that your modem and serial port support the Port Speed value you intend to set.

1. Load the %SystemRoot%\SYSTEM32\RAS\SERIAL.INI into a text editor, for example, NOTEPAD.EXE.
2. Change the INITIALBPS parameter to the desired value.
3. Save SERIAL.INI.
4. Run RasAdmin.
5. From the Server menu, choose Stop Remote Access Service.
6. From the Server menu, choose Start Remote Access Service.