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This chapter covers the following topics that you need to master as a CCNP:
·
Modem signaling--This section covers the transfer of data, the flow control for the
signal and the modem, and the call termination methods that are defined by the
modem signal pins.
·
Modem configuration using reverse Telnet--This section describes reverse Telnet,
which provides a method to communicate with a device that is attached to an
asynchronous port on the router.
·
Router line numbering--In this section, each router asynchronous interface has an
associated line number where the physical and datalink parameters are configured.
The line numbering is different between the fixed and nonfixed configuration router
models.
·
Basic asynchronous configuration--This section covers the configuration of the
physical interface so that it can communicate with the attached device. In the same
way that you configure a COM port to talk to a modem on a PC, you must declare to
a router the parameters that match the modem settings.
·
Configuration of the attached modem--In this section, you learn that a modem
must be configured to answer a call and to provide the correct signalling for the
telephone company. This is done using the modem command language, which uses
the AT command set.
·
Chat scripts to control modem connections--This section covers chat scripts,
which provide a way to dictate to the modem how to place a call, answer an incoming
call, and handle a current connection.