配置实例：
　　　maui-rtr-10 (Client)
　　maui-rtr-10#show running-config
　　Building configuration...
　　
　　Current configuration:
　　!
　　version 12.1
　　service timestamps debug datetime msec
　　service timestamps log datetime msec
　　no service password-encryption
　　!
　　hostname maui-rtr-10
　　!
　　aaa new-model
　　aaa authentication login default local
　　aaa authentication login NO_AUTHEN none
　　aaa authentication ppp default local
　　!--- This is the basic AAA configuration for ppp calls
　　enable secret 5
　　!
　　username admin password 0
　　username maui-rtr-11 password 0 cisco
　　!--- Username for remote router (maui-rtr-11) and shared secret password Shared
　　!--- secret (used for CHAP authentication)must be the same on both sides
　　!
　　ip subnet-zero
　　!
　　chat-script Dialout ABORT ERROR ABORT BUSY "" "AT" OK "ATDT \T" TIMEOUT 45 CONNECT \c
　　!--- chat script named "Dialout" is used for the backup dialout.
　　modemcap entry MY_USR_MODEM:MSC=&F1S0=1
　　!--- Modemcap named "MY_USR_MODEM" will be applied to the AUX port line interface.
　　!--- This modemcap was created using the command:
　　!--- modemcap edit MY_USR_MODEM miscellaneous &F1S0=1
　　!--- Refer to the Modem-Router Connection Guide for more information
　　!
　　interface Loopback0
　　ip address 172.17.1.1 255.255.255.0
　　!
　　interface Ethernet0/0
　　ip address 172.16.1.1 255.255.255.0
　　no keepalive
　　!
　　interface Serial0/0
　　no ip address
　　shutdown
　　no fair-queue
　　!
　　interface Serial0/1
　　!--- Primary Link
　　ip address 192.168.10.2 255.255.255.252
　　encapsulation ppp
　　clockrate 64000
　　ppp authentication chap
　　!
　　interface Async65
　　!--- Async interface corresponding to the AUX Port(backup link)
　　!--- This was determined using the show line command
　　ip unnumbered Loopback0
　　!--- This assigns the loopback 0 ip address to this interface.
　　!--- The central router will have a dialer map to this loopback address
　　encapsulation ppp
　　dialer in-band
　　!--- Allow DDR on this interface
　　dialer idle-timeout 30
　　!--- idle timeout(in seconds)for this link
　　!--- dialer watch checks the status of the primary link
　　!--- every time the idle-timeout expires
　　dialer watch-disable 15
　　!--- delays disconnecting the backup interface (for 15 seconds)after
　　!--- the primary interface is found to be up
　　dialer map ip 172.22.1.1 name maui-rtr-11 broadcast 84007
　　!--- dialer map for the AUX Port interface of the central router
　　!--- Remember that the central router's AUX port is unnumbered to its Loopback 0
　　dialer map ip 172.22.53.0 name maui-rtr-11 broadcast 84007
　　!--- map statement for the route/network being watched
　　!--- address must exactly match the network configured with
　　!--- the dialer watch-list command
　　!--- dials the phone number specified when the watched route disappears
　　dialer watch-group 8
　　!--- Enable dialer watch on this backup interface
　　!--- Watch the route specified with dialer watch-list 8
　　dialer-group 1
　　!--- apply interesting traffic defined in dialer-list 1
　　async default routing
　　!--- permit routing over the async interface
　　!--- this is required for a routing protocol to run across the async link
　　async mode interactive
　　ppp authentication chap
　　!
　　router ospf 5
　　network 172.16.1.0 0.0.0.255 area 0
　　network 172.17.1.0 0.0.0.255 area 0
　　network 192.168.10.0 0.0.0.3 area 0
　　!
　　ip classless
　　no ip http server
　　!
　　access-list 101 remark Define Interesting Traffic
　　access-list 101 deny ospf any any
　　!--- Mark OSPF as uninteresting
　　!--- This will prevent OSPF hellos from keeping the link up
　　access-list 101 permit ip any any
　　!
　　dialer watch-list 8 ip 172.22.53.0 255.255.255.0
　　!--- define the route to be watched
　　!--- this exact route(including subnet mask) must exist in the routing table
　　dialer-list 1 protocol ip list 101
　　!--- interesting traffic is defined by access-list 101
　　!--- This is applied to BRI0 using dialer-group 1
　　!
　　line con 0
　　login authentication NO_AUTHEN
　　transport input none
　　line Aux 0
　　!--- line configuration for the AUX port
　　exec-timeout 0 0
　　!--- disable exec timeout on the interface
　　autoselect ppp
　　script dialer Dialout
　　!--- Use the chat script named "Dialout" for outgoing calls.
　　modem InOut
　　!--- enable incoming and outgoing calls
　　modem autoconfigure type MY_USR_MODEM
　　!--- Apply the modemcap MY_USR_MODEM (configured previously) to initalize the modem.
　　transport input all
　　stopbits 1
　　!--- Improve throughput by reducing async framing overhead.
　　speed 115200
　　!--- AUX port on the 2600 supports a speed of 115200.
　　!--- Note: If you are routing through the AUX port, each character generates a
　　!--- processor interrupt. This is an abnormally high load on the CPU, which can be
　　!--- resolved by using a lower AUX port speed.
　　flowcontrol hardware
　　!--- This configures RTS/CTS flow control.
　　line vty 0 4
　　!
　　no scheduler allocate
　　end
　　
　　maui-rtr-11 (Central Site)
　　maui-rtr-11#show running-config
　　Building configuration...
　　
　　Current configuration:
　　!
　　version 12.1
　　service timestamps debug uptime
　　service timestamps log uptime
　　no service password-encryption
　　!
　　hostname maui-rtr-11
　　!
　　aaa new-model
　　aaa authentication login default local
　　aaa authentication login NO_AUTHEN none
　　aaa authentication ppp default local
　　!--- This is the basic AAA configuration for ppp calls
　　enable secret 5
　　!
　　username admin password 0
　　username maui-rtr-10 password 0 cisco
　　!--- Username for remote router (maui-rtr-10) and shared secret!--- Shared secret(used for CHAP authentication) must be the same on both sides
　　!
　　memory-size iomem 30
　　!
　　ip subnet-zero
　　!
　　modemcap entry MY_USR_MODEM:MSC=&F1S0=1
　　!--- Modemcap (MY_USR_MODEM) will be applied to the AUX port line interface
　　!--- This modemcap was created using the command:
　　!--- modemcap edit MY_USR_MODEM miscellaneous &F1S0=1
　　!--- Refer to the Modem-Router Connection Guide for more information
　　!
　　interface Loopback0
　　ip address 172.22.1.1 255.255.255.0
　　!
　　interface FastEthernet0/0
　　!--- Interface to corporate network
　　ip address 172.22.53.105 255.255.255.0
　　no keepalive
　　duplex auto
　　speed auto
　　!
　　! <<-- irrelevant output removed
　　!
　　interface Serial0/1
　　!--- Primary Link
　　ip address 192.168.10.1 255.255.255.252
　　encapsulation ppp
　　ppp authentication chap
　　!
　　interface Serial0/2
　　no ip address
　　shutdown
　　!
　　interface Async65
　　!--- Async interface corresponding to the AUX Port(backup link)
　　!--- This was determined using the show line command
　　ip unnumbered Loopback0
　　!--- Use Loopback 0 address for this interface
　　!--- The remote router will have a dialer map to this loopback address
　　encapsulation ppp
　　dialer in-band
　　dialer idle-timeout 900
　　dialer map ip 172.17.1.1 name