Installing and Administering PPP

132 Chapter 5
Security Techniques
Dial-Back
Reversing Instructions with \m Option
After the disconnection period, through the ‘send’ phase option \m, pppd
tells the system’s serial drivers to reverse the first instruction and
respect the modem’s full variety of control. For example, to dial into a
system protected by a dial-back modem, the Systems chat script might
be written like this:
#
# This connects to a system protected by a Telebit T3000 callback
# modem
# with S46=2.
#
server Any ACU 38400 19071234567 TIMEOUT 60 \
ENTER\sPASSWORD: my_modem_password\M \
ENTER\SPASSWORD: my_modem_password\m \
login: my_login_name password: my_login_password