4-13
Switch Setup
4.8 Modem Configuration
All Cabletron ATM switches support modem access. This may be useful if a
switch is installed in a remote location where direct, physical access to the
switch is not possible or practical. Keep the following in mind when using a
modem to access a Cabletron ATM switch:
• To allow the Cabletron ATM switch to communicate with the modem,
a Null-Modem Adapter must be installed on the factory-supplied
serial cable.
• The Cabletron ATM switch will not disconnect an ATM Management
Interface (AMI) session on loss-of-carrier; therefore, you must ensure
that you have completely exited from an open AMI session before
disconnecting the modem session.
To allow a modem to work with a Cabletron ATM switch, you must complete
two sets of configurations. First, the speed of the serial port on the Cabletron
ATM switch must be set to match that of the attached modem and, second,
the modem parameters must be configured correctly.

4.8.1 Modem Parameters

You should use a Hayes-compatible modem, as the configuration parameters
supplied here are applicable to this type of modem. The following parameters
should be applied to your Hayes-compatible modem to allow it to function
properly with the switch’s serial port. You may attach a tty device to the
modem to set these parameters.
Setting Comment
ATE0 Turn off Echoing
ATQ1 No Return Codes
AT&C0 Force Carrier Detect (CD) High
AT&D0 Ignore Data Terminal Ready (DTR)
AT&W Save Modem Configuration