52
CONFIGURING MODEM
This chapter covers the following topics:
■ Modem Function Provided by 3Com Routers
■ Configuring a Modem
■ Displaying and Debugging a Modem
■ Modem Configuration Examples
■ Troubleshooting
Modem Function
Provided by 3Com
Routers
To offer the optimal flexibility, 3Com routers provide the following modem
management functions:
■ Provide the scripts (modem script) for modem management to enable the user
to better control the modems connected to the router. A modem script can be
executed by the following two means:
■ Executes a modem script directly through the script-string command to
initialize the modem or other configurations.
■ Triggers the modem script with particular events, such as router startup,
modem dial-in connection, and the
start-chat command.
■ Using the script along with the related commands can enhance the remote
configuration function of router. If the asynchronous serial interface works in
flow mode, the user can establish a remote connection to the interface
through the dumb terminal or modem dialup, to configure and manage the
router.
■ Directly send AT commands to the modem via the serial interface for managing
the modem.
■ Interwork with the equipment of other equipment vendors. That is, the
asynchronous serial interfaces of the participating parties are working in the
flow mode and interconnected through modems.
■ Provides rich debugging information for modem monitoring and maintenance.
Modem Script 3Com routers provide t modem scripts, which are mainly used for:
■ Flexibly controlling the modems of different models. For example, using
different initialization AT commands able to interoperate with 3Com routers.
■ Implementing the interactive login to remote systems. Interactive negotiation
of the scripts can enable the system enters different link states. For example,
after the asynchronous serial interfaces on the two routers set up a connection
through the modem, routers can negotiate the protocol to be encapsulated
with the physical link and its operating parameters.