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Basic Asynchronous Configuration 81
The login local command is the same for this line as it is for the console and AUX ports. The
Login local command tells the physical line to request a username/password pair when a
connection is made and to look locally on the router for a matching username xxxx password
yyyy pair that has been configured in global mode (xxxx and yyyy represent a freely chosen
username and password combination).
The autoselect during-login and autoselect ppp commands automatically start the PPP
protocol and issue a carriage return so that the user is prompted for the login. This feature
became available in IOS Software Release 11.0. Prior to this "during-login" feature, the dial-
up user was required to issue an exec command or press the Enter key to start the session.
The modem InOut command enables both incoming and outgoing calls. The alternative to this
command is the default no modem inout command, which yields no control over the modem.
The modem autoconfigure type usr_sportster command uses the modemcap database
usr_sportster
entry to initialize the modem. We further discuss this initialization later in the
chapter.
The transport input all command enables the processing of any protocols on the line. This
command defines which protocols to use to connect to a line. The default command prior to
11.1 was all; the default with 11.1 is none.
In the router configuration, the number of stopbits must be the same for both communicating
DCE devices. Remember that the physical-layer parameters must match for the physical layer
to be established. Failure to do so prevents the upper layers from beginning negotiation.
In Example 4-6, rxspeed and txspeed are shown as separate commands. The speed command,
however, sets both transmit and receive speeds and locks the speed between the modem and the
DTE device. Failure to lock or control the DTE-to-DCE speed allows the speed of local
communication to vary with the line speed negotiated between the DCE devices. This limits the
capability of the DTE-to-DCE flow control.
The flowcontrol hardware command specifies that the RTS and CTS be honored for flow
control.
Example 4-6
Router Configuration Connecting USR Sportster Modem on Physical Line 2
line 2
autoselect during-login
autoselect ppp
login local
modem InOut
modem autoconfigure type usr_sportster
transport input all
stopbits 1
rxspeed 115200
txspeed 115200
flowcontrol hardware