to signal. The key is in the ip route commands and the new dialer map command. Of course,
there are unique ISDN telephone numbers for both LosAngeles and GothamCity. Because the
static routes will direct the router to send the packet to either 172.16.2.1 or 172.16.2.3, all that
is needed is a mapping between these next-hop addresses and their respective ISDN telephone
numbers. The dialer map command does exactly that. Example 8-29 shows the mostly
complete configuration.
dial to LosAngeles would occur. Conversely, if the interesting packet were routed to 172.16.2.3,
the dial to GothamCity would occur. The definition of interesting is expanded to include packets
to the FTP server in GothamCity.
authentication was configured. PAP or CHAP is required if dialing to more than one site with
ISDN--and PAP and CHAP require PPP. The user name expected from the other router is
coded in the corresponding dialer map command.
other point-to-point serial link, there is no true data link broadcast. If a broadcast must be sent
on the interface, however, it is necessary to issue the broadcast command to tell the interface
to forward the packet across the link.
ip route 172.16.4.0 255.255.255.0 172.16.2.3
! Added usernames for CHAP support!
username LosAngeles password Clark
username GothamCity password Bruce
access-list 101 permit tcp any host 172.16.3.1 eq 80
! Added next statement to make The Client's FTP connection interesting!
access-list 101 permit tcp any host 172.16.4.1 eq 21
!
dialer-list 2 protocol ip list 101
!
interface bri 0
ip address 172.16.2.2 255.255.255.0
encapsulation ppp
ppp authentication chap
dialer map ip 172.16.2.1 broadcast name LosAngeles 14045551234
dialer map ip 172.16.2.3 broadcast name GothamCity 1999999999901
dialer-group 2
!
router igrp 6
network 172.16.0.0