third example

Configure
In this section, you are presented with the information to configure the features described in this document.

This document uses this network setup:

Network Diagram

This document uses this network setup:

Configurations
This document uses these configurations:
C2503
C4000

C2503
C2503#write terminal
######
Current configuration:
!
version 10.2
!
hostname C2503
!
enable password test
!
username C4000 password cisco
isdn switch-type basic-dms100
!
interface Ethernet0
ip address 172.16.10.1 255.255.255.0
!
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.1 255.255.255.0
encapsulation ppp
bandwidth 56
dialer idle-timeout 300
dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155551234
dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155556789
dialer hold-queue 5
dialer load-threshold 100
dialer-group 1
isdn spid1 408555432101 5554321
isdn spid2 408555987601 5559876
ppp authentication chap
!
router igrp 1
network 172.16.0.0
!
ip route 192.168.24.0 255.255.255.0 172.16.20.2
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255
!
!
dialer-list 1 list 100
!
line con 0
line aux 0
line vty 0 4
password test
login
!
end

C4000
C4000#write terminal
######
Current configuration:
!
version 10.2
!
hostname C4000
!
enable password test
!
username C2503 password cisco
!--- See the username explanation in the
isdn switch-type basic-dms100
!
interface Ethernet0
ip address 192.168.24.65 255.255.255.0
!
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.2 255.255.255.0
encapsulation ppp
bandwidth 56
dialer idle-timeout 300
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085554321
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085559876
dialer hold-queue 5
dialer load-threshold 100
dialer-group 1
isdn spid1 415555123401 5551234
isdn spid2 415555678901 5556789
ppp authentication chap
!
router igrp 1
network 172.16.0.0
network 192.168.24.0
!
ip route 172.16.10.0 255.255.255.0 172.16.20.1
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255
!
!
dialer-list 1 list 100
!
line con 0
line aux 0
line vty 0 4
password test
login
!
end
Explanation of the C2503 Configuration
C2503#write terminal
######
Current configuration:
!
version 10.2
!
hostname C2503
!
enable password test
!
username C4000 password cisco
The username C4000 is the host name of the remote router. The dialer map command, which this section explains, uses this username. The username is not case sensitive during authentication. However, the name that you configure with the dialer map command is case sensitive. You must exactly match the host name of the remote router, which is "C4000".
Note: In router C2503, the name that you configure with the username command must exactly match the name that you configure with the dialer map command. You issue the username command in global configuration mode.
The Challenge Handshake Authentication Protocol (CHAP) authentication process uses the password. The password is case sensitive and must match the remote router password exactly.
Note: In order to avoid confusion, this configuration example uses the unencrypted form of the password cisco. In the actual configuration, the password appears in its encrypted form: 7 13061E010803. In this password, 7 denotes the encryption type and 13061E010803 is the encrypted form of the password cisco. When you issue or make changes to the username command, always enter the password in its unencrypted form and do not enter the encryption type (7). The encryption type is set automatically.
isdn switch-type basic-dms100—The ISDN switch type must match the equipment of your carrier. If you change the switch type, you must reload the router in order for the new switch type to take effect.
interface Ethernet0
ip address 172.16.10.1 255.255.255.0
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.1 255.255.255.0
encapsulation ppp—Use PPP encapsulation instead of High-Level Data Link Control (HDLC) in order to allow the use of CHAP authentication.
bandwidth 56—The default bandwidth setting for a BRI interface is 64 kbps. If you configure your dialer map statements with the speed 56 option, include the bandwidth statement.
Note: This command does not control the speed of your ISDN line. The command sets the correct reference point for:
The BRI port show interface statistics
The dialer load-threshold command
Interior Gateway Routing Protocol (IGRP)/Enhanced IGRP (EIGRP) routing metrics
dialer idle-timeout 300—This command sets the number of seconds that the ISDN connection remains open if no interesting traffic is being routed. The timer is reset each time that an interesting packet is forwarded.
dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155551234
dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155556789
Use the dialer map command with CHAP authentication in order to place the initial call to the remote router when interesting traffic is forwarded to the BRI interface. When the connection becomes active, the dialer idle-timeout command determines the length of time for the connection to remain active. A dialer map statement is necessary for each ISDN phone number that will be called. However, be aware that two dialer map statements that point to the same location can activate both B channels when you may only want to use one channel.
The command parameters for this example are:
172.16.20.2—The IP address of the remote router BRI interface
In order to determine this address, issue the show interface bri 0 command at the remote router console prompt.
name C4000—The host name of the remote router
The name is case sensitive and must match the name that you configure for the username command.
speed 56—Sets the dialer speed to 56 kbps for ISDN circuits that are not 64 kbps end to end
Include this parameter in the dialer map statements of both routers. Most installations in North America must be configured for 56 kbps.
broadcast—Allows the forwarding of broadcast packets
Unless the dialer-list command specifies broadcast packets as interesting packets, the packets are only forwarded when the ISDN link is active.
14155551234 and 14155556789—The remote router ISDN telephone numbers
dialer hold-queue 5—This command allows interesting packets to be queued until establishment of the ISDN connection. In this example, five interesting packets are to be queued.
dialer load-threshold 100—This command configures bandwidth on demand. The command sets the maximum load before the dialer places another call through the second B channel. The load is the calculated weighted average load value for the interface, where 1 is unloaded and 255 is fully loaded. The actual load value to configure depends on the characteristics of your particular network. In this example, the second B channel is activated when the load reaches 39 percent of maximum utilization, which is 100 divided by 255.
dialer-group 1—The dialer-group 1 command enables dialer list 1 on the BRI interface, which determines which packets are interesting and will activate the ISDN connection.
isdn spid1 408555432101 5554321
isdn spid2 408555987601 5559876
Use the isdn spid commands if your carrier assigns service profile identifiers (SPIDs) to your ISDN lines.
ppp authentication chap—This command enables CHAP authentication.
router igrp 1
network 172.16.0.0
ip route 192.168.24.0 255.255.255.0 172.16.20.2—This ip route command creates a static route to the remote router network via the remote router BRI interface. This is a requirement because dynamic routes are lost when the ISDN link is down.
The command parameters for this example are:
192.168.24.0—The target network
255.255.255.0—The target network mask
A 255 in an octet position specifies that an exact match for that octet is necessary. A 0 in an octet position specifies that any value matches.
172.16.20.2—The address of the next hop that can be used to reach the target network
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255—This access-list command determines which IP packets are interesting and will activate the ISDN link. The access list to create depends on your particular network design.
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0—This access-list command defines all broadcast packets as uninteresting.
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0255.255.255.255—This access-list command defines all other IP packets as interesting.
dialer-list 1 list 100—This command points to access list 100, which determines which IP packets are interesting.
line con 0
line aux 0
line vty 0 4
password test
login
!
end
Explanation of the C4000 Configuration
C4000#write terminal
######
Current configuration:
!
version 10.2
!
hostname C4000
!
enable password test
!
username C2503 password cisco
The username C2503 is the host name of the remote router. The dialer map command, which this section explains, uses this username. The username is not case sensitive during authentication. However, the name that you configure with the dialer map command is case sensitive. You must exactly match the host name of the remote router, which is "C2503".
Note: In router C4000, the name that you configure with the username must exactly match the name that you configure with the dialer map command. You issue the username command in global configuration mode.
The CHAP authentication process uses the password. The password is case sensitive and must match the remote router password exactly.
Note: In order to avoid confusion, this configuration example uses the unencrypted form of the password cisco. In the actual configuration, the password appears in its encrypted form: 7 13061E010803. In this password, 7 denotes the encryption type and 13061E010803 is the encrypted form of the password cisco. When you issue or make changes to the username command, always enter the password in its unencrypted form and do not enter the encryption type (7). The encryption type is set automatically.
isdn switch-type basic-dms100—The ISDN switch type must match the equipment of your carrier. If you change the switch type, you must reload the router in order for the new switch type to take effect.
interface Ethernet0
ip address 192.168.24.65 255.255.255.0
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.2 255.255.255.0
encapsulation ppp
encapsulation ppp—Use PPP encapsulation instead of HDLC in order to allow the use of CHAP authentication.
bandwidth 56—The default bandwidth setting for a BRI interface is 64 kbps. If you configure your dialer map statements with the speed 56 option, include the bandwidth statement.
Note: This command does not control the speed of your ISDN line. The command sets the correct reference point for:
The BRI port show interface statistics
The dialer load-threshold command
IGRP/EIGRP routing metrics
dialer idle-timeout 300—This command sets the number of seconds that the ISDN connection remains open if no interesting traffic is being routed. The timer is reset each time that an interesting packet is forwarded.
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085554321
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085559876
Use the dialer map command with CHAP authentication in order to place the initial call to the remote router when interesting traffic is forwarded to the BRI interface. When the connection becomes active, the dialer idle-timeout command determines the length of time for the connection to remain active. A dialer map statement is necessary for each ISDN phone number that will be called. However, be aware that two dialer map statements that point to the same location can activate both B channels when you may only want to use one channel.
The command parameters for this example are:
172.16.20.1—The IP address of the remote router BRI interface
In order to determine this address, issue the show interface bri 0 command at the remote router console prompt.
name C2503—The host name of the remote router
The name is case sensitive and must match the name that you configure for the username command.
speed 56—Sets the dialer speed to 56 kbps for ISDN circuits that are not 64 kbps end to end
Include this parameter in the dialer map statements of both routers. Most installations in North America must be configured for 56 kbps.
broadcast—Allows the forwarding of broadcast packets
Unless the dialer-list command specifies broadcast packets as interesting packets, the packets are only forwarded when the ISDN link is active.
14085554321 and 14085559876—The remote router ISDN telephone numbers
dialer hold-queue 5 —This command allows interesting packets to be queued until establishment of the ISDN connection. In this example, five interesting packets are to be queued.
dialer load-threshold 100—This command configures bandwidth on demand. The command sets the maximum load before the dialer places another call through the second B channel. The load is the calculated weighted average load value for the interface, where 1 is unloaded and 255 is fully loaded. The actual load value to configure depends on the characteristics of your particular network. In this example, the second B channel is activated when the load reaches 39 percent of maximum utilization, which is 100 divided by 255.
dialer-group 1—The dialer-group 1 command enables the dialer list 1 on the BRI interface, which determines which packets are interesting and will activate the ISDN connection.
isdn spid1 415555123401 5551234
isdn spid2 415555678901 5556789
Use the isdn spid commands if your carrier assigns SPIDs to your ISDN lines.
ppp authentication chap—This command enables CHAP authentication.
router igrp 1
network 172.16.0.0
network 192.168.24.0
ip route 172.16.10.0 255.255.255.0 172.16.20.1—This ip route command creates a static route to the remote router network via the remote router BRI interface. This is a requirement because dynamic routes are lost when the ISDN link is down.
The command parameters for this example are:
172.16.0.0—The target network
255.255.0.0—The target network mask
A 255 in an octet position specifies that an exact match for that octet is necessary. A 0 in an octet position specifies that any value matches.
172.16.20.1—The address of the next hop that can be used to reach the target network
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255—This access-list command determines which IP packets are interesting and will activate the ISDN link. The access list to create depends on your particular network design.
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0—This access-list command defines all broadcast packets as uninteresting.
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255—This access-list command defines all other IP packets as interesting.
dialer-list 1 list 100—This command points to access list 100, which determines which IP packets are interesting.
line con 0
line aux 0
line vty 0 4
password test
login
!
end



Configurations
This document uses these configurations:

C2503

C4000

C2503

C2503#write terminal
######
Current configuration:
!
version 10.2
!
hostname C2503
!
enable password test
!
username C4000 password cisco

!--- See the username explanation in the
!--- Explanation of the C2503 Configuration section of this document.

isdn switch-type basic-dms100
!
interface Ethernet0
ip address 172.16.10.1 255.255.255.0
!
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.1 255.255.255.0
encapsulation ppp
bandwidth 56
dialer idle-timeout 300
dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155551234
dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155556789
dialer hold-queue 5
dialer load-threshold 100
dialer-group 1
isdn spid1 408555432101 5554321
isdn spid2 408555987601 5559876
ppp authentication chap
!
router igrp 1
network 172.16.0.0
!
ip route 192.168.24.0 255.255.255.0 172.16.20.2
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255
!
!
dialer-list 1 list 100
!
line con 0
line aux 0
line vty 0 4
password test
login
!
end


C4000

C4000#write terminal
######
Current configuration:
!
version 10.2
!
hostname C4000
!
enable password test
!
username C2503 password cisco

!--- See the username explanation in the
!--- Explanation of the C4000 Configuration section of this document.

isdn switch-type basic-dms100
!
interface Ethernet0
ip address 192.168.24.65 255.255.255.0
!
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.2 255.255.255.0
encapsulation ppp
bandwidth 56
dialer idle-timeout 300
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085554321
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085559876
dialer hold-queue 5
dialer load-threshold 100
dialer-group 1
isdn spid1 415555123401 5551234
isdn spid2 415555678901 5556789
ppp authentication chap
!
router igrp 1
network 172.16.0.0
network 192.168.24.0
!
ip route 172.16.10.0 255.255.255.0 172.16.20.1
access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0
access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255
!
!
dialer-list 1 list 100
!
line con 0
line aux 0
line vty 0 4
password test
login
!
end



Explanation of the C2503 Configuration
C2503#write terminal
######
Current configuration:
!
version 10.2
!
hostname C2503
!
enable password test
!
username C4000 password ciscoThe username C4000 is the host name of the remote router. The dialer map command, which this section explains, uses this username. The username is not case sensitive during authentication. However, the name that you configure with the dialer map command is case sensitive. You must exactly match the host name of the remote router, which is "C4000".

Note: In router C2503, the name that you configure with the username command must exactly match the name that you configure with the dialer map command. You issue the username command in global configuration mode.

The Challenge Handshake Authentication Protocol (CHAP) authentication process uses the password. The password is case sensitive and must match the remote router password exactly.

Note: In order to avoid confusion, this configuration example uses the unencrypted form of the password cisco. In the actual configuration, the password appears in its encrypted form: 7 13061E010803. In this password, 7 denotes the encryption type and 13061E010803 is the encrypted form of the password cisco. When you issue or make changes to the username command, always enter the password in its unencrypted form and do not enter the encryption type (7). The encryption type is set automatically.

isdn switch-type basic-dms100—The ISDN switch type must match the equipment of your carrier. If you change the switch type, you must reload the router in order for the new switch type to take effect.

interface Ethernet0
ip address 172.16.10.1 255.255.255.0

interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.1 255.255.255.0encapsulation ppp—Use PPP encapsulation instead of High-Level Data Link Control (HDLC) in order to allow the use of CHAP authentication.

bandwidth 56—The default bandwidth setting for a BRI interface is 64 kbps. If you configure your dialer map statements with the speed 56 option, include the bandwidth statement.

Note: This command does not control the speed of your ISDN line. The command sets the correct reference point for:

The BRI port show interface statistics

The dialer load-threshold command

Interior Gateway Routing Protocol (IGRP)/Enhanced IGRP (EIGRP) routing metrics

dialer idle-timeout 300—This command sets the number of seconds that the ISDN connection remains open if no interesting traffic is being routed. The timer is reset each time that an interesting packet is forwarded.

dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155551234

dialer map ip 172.16.20.2 name C4000 speed 56 broadcast 14155556789

Use the dialer map command with CHAP authentication in order to place the initial call to the remote router when interesting traffic is forwarded to the BRI interface. When the connection becomes active, the dialer idle-timeout command determines the length of time for the connection to remain active. A dialer map statement is necessary for each ISDN phone number that will be called. However, be aware that two dialer map statements that point to the same location can activate both B channels when you may only want to use one channel.

The command parameters for this example are:

172.16.20.2—The IP address of the remote router BRI interface

In order to determine this address, issue the show interface bri 0 command at the remote router console prompt.

name C4000—The host name of the remote router

The name is case sensitive and must match the name that you configure for the username command.

speed 56—Sets the dialer speed to 56 kbps for ISDN circuits that are not 64 kbps end to end

Include this parameter in the dialer map statements of both routers. Most installations in North America must be configured for 56 kbps.

broadcast—Allows the forwarding of broadcast packets

Unless the dialer-list command specifies broadcast packets as interesting packets, the packets are only forwarded when the ISDN link is active.

14155551234 and 14155556789—The remote router ISDN telephone numbers

dialer hold-queue 5—This command allows interesting packets to be queued until establishment of the ISDN connection. In this example, five interesting packets are to be queued.

dialer load-threshold 100—This command configures bandwidth on demand. The command sets the maximum load before the dialer places another call through the second B channel. The load is the calculated weighted average load value for the interface, where 1 is unloaded and 255 is fully loaded. The actual load value to configure depends on the characteristics of your particular network. In this example, the second B channel is activated when the load reaches 39 percent of maximum utilization, which is 100 divided by 255.

dialer-group 1—The dialer-group 1 command enables dialer list 1 on the BRI interface, which determines which packets are interesting and will activate the ISDN connection.

isdn spid1 408555432101 5554321

isdn spid2 408555987601 5559876

Use the isdn spid commands if your carrier assigns service profile identifiers (SPIDs) to your ISDN lines.

ppp authentication chap—This command enables CHAP authentication.

router igrp 1
network 172.16.0.0ip route 192.168.24.0 255.255.255.0 172.16.20.2—This ip route command creates a static route to the remote router network via the remote router BRI interface. This is a requirement because dynamic routes are lost when the ISDN link is down.

The command parameters for this example are:

192.168.24.0—The target network

255.255.255.0—The target network mask

A 255 in an octet position specifies that an exact match for that octet is necessary. A 0 in an octet position specifies that any value matches.

172.16.20.2—The address of the next hop that can be used to reach the target network

access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0

access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255—This access-list command determines which IP packets are interesting and will activate the ISDN link. The access list to create depends on your particular network design.

access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0—This access-list command defines all broadcast packets as uninteresting.

access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0255.255.255.255—This access-list command defines all other IP packets as interesting.

dialer-list 1 list 100—This command points to access list 100, which determines which IP packets are interesting.

line con 0
line aux 0
line vty 0 4
password test
login
!
endExplanation of the C4000 Configuration
C4000#write terminal
######
Current configuration:
!
version 10.2
!
hostname C4000
!
enable password test
!
username C2503 password ciscoThe username C2503 is the host name of the remote router. The dialer map command, which this section explains, uses this username. The username is not case sensitive during authentication. However, the name that you configure with the dialer map command is case sensitive. You must exactly match the host name of the remote router, which is "C2503".

Note: In router C4000, the name that you configure with the username must exactly match the name that you configure with the dialer map command. You issue the username command in global configuration mode.

The CHAP authentication process uses the password. The password is case sensitive and must match the remote router password exactly.

Note: In order to avoid confusion, this configuration example uses the unencrypted form of the password cisco. In the actual configuration, the password appears in its encrypted form: 7 13061E010803. In this password, 7 denotes the encryption type and 13061E010803 is the encrypted form of the password cisco. When you issue or make changes to the username command, always enter the password in its unencrypted form and do not enter the encryption type (7). The encryption type is set automatically.

isdn switch-type basic-dms100—The ISDN switch type must match the equipment of your carrier. If you change the switch type, you must reload the router in order for the new switch type to take effect.

interface Ethernet0
ip address 192.168.24.65 255.255.255.0

interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
interface BRI0
ip address 172.16.20.2 255.255.255.0

encapsulation pppencapsulation ppp—Use PPP encapsulation instead of HDLC in order to allow the use of CHAP authentication.

bandwidth 56—The default bandwidth setting for a BRI interface is 64 kbps. If you configure your dialer map statements with the speed 56 option, include the bandwidth statement.

Note: This command does not control the speed of your ISDN line. The command sets the correct reference point for:

The BRI port show interface statistics

The dialer load-threshold command

IGRP/EIGRP routing metrics

dialer idle-timeout 300—This command sets the number of seconds that the ISDN connection remains open if no interesting traffic is being routed. The timer is reset each time that an interesting packet is forwarded.

dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085554321
dialer map ip 172.16.20.1 name C2503 speed 56 broadcast 14085559876 Use the dialer map command with CHAP authentication in order to place the initial call to the remote router when interesting traffic is forwarded to the BRI interface. When the connection becomes active, the dialer idle-timeout command determines the length of time for the connection to remain active. A dialer map statement is necessary for each ISDN phone number that will be called. However, be aware that two dialer map statements that point to the same location can activate both B channels when you may only want to use one channel.

The command parameters for this example are:

172.16.20.1—The IP address of the remote router BRI interface

In order to determine this address, issue the show interface bri 0 command at the remote router console prompt.

name C2503—The host name of the remote router

The name is case sensitive and must match the name that you configure for the username command.

speed 56—Sets the dialer speed to 56 kbps for ISDN circuits that are not 64 kbps end to end

Include this parameter in the dialer map statements of both routers. Most installations in North America must be configured for 56 kbps.

broadcast—Allows the forwarding of broadcast packets

Unless the dialer-list command specifies broadcast packets as interesting packets, the packets are only forwarded when the ISDN link is active.

14085554321 and 14085559876—The remote router ISDN telephone numbers

dialer hold-queue 5 —This command allows interesting packets to be queued until establishment of the ISDN connection. In this example, five interesting packets are to be queued.

dialer load-threshold 100—This command configures bandwidth on demand. The command sets the maximum load before the dialer places another call through the second B channel. The load is the calculated weighted average load value for the interface, where 1 is unloaded and 255 is fully loaded. The actual load value to configure depends on the characteristics of your particular network. In this example, the second B channel is activated when the load reaches 39 percent of maximum utilization, which is 100 divided by 255.

dialer-group 1—The dialer-group 1 command enables the dialer list 1 on the BRI interface, which determines which packets are interesting and will activate the ISDN connection.

isdn spid1 415555123401 5551234

isdn spid2 415555678901 5556789

Use the isdn spid commands if your carrier assigns SPIDs to your ISDN lines.

ppp authentication chap—This command enables CHAP authentication.

router igrp 1
network 172.16.0.0
network 192.168.24.0ip route 172.16.10.0 255.255.255.0 172.16.20.1—This ip route command creates a static route to the remote router network via the remote router BRI interface. This is a requirement because dynamic routes are lost when the ISDN link is down.

The command parameters for this example are:

172.16.0.0—The target network

255.255.0.0—The target network mask

A 255 in an octet position specifies that an exact match for that octet is necessary. A 0 in an octet position specifies that any value matches.

172.16.20.1—The address of the next hop that can be used to reach the target network

access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0.0

access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255—This access-list command determines which IP packets are interesting and will activate the ISDN link. The access list to create depends on your particular network design.

access-list 100 deny ip 0.0.0.0 255.255.255.255 255.255.255.255 0.0.0—This access-list command defines all broadcast packets as uninteresting.

access-list 100 permit ip 0.0.0.0 255.255.255.255 0.0.0.0 255.255.255.255—This access-list command defines all other IP packets as interesting.

dialer-list 1 list 100—This command points to access list 100, which determines which IP packets are interesting.

line con 0
line aux 0
line vty 0 4
password test
login
!
end

second example of isdn configration

Sample Configuration: Basic ISDN Configuration

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Sample Configuration: Basic ISDN Configuration
Document ID: 14221 -->
Contents
Introduction Prerequisites Requirements Components Used Conventions Background Information Configure Network Diagram Configurations Key Configuration Parameters Verify Troubleshoot NetPro Discussion Forums - Featured Conversations Related Information
Introduction
This document provides a sample configuration for basic ISDN. It also explains of some of the ISDN configuration commands. For more information about the commands, see the Router Products Command Reference.
Prerequisites
Requirements
Readers of this document should have basic knowledge of IP routing. For more information, see IP Addressing and Subnetting for New Users.
Components Used
This document is not restricted to specific software and hardware versions.
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
Conventions
For more information on document conventions, refer to Cisco Technical Tips Conventions.
Background Information
This document uses a Cisco 3103 (1E/1BRI) in the example. It is configured to route IP over a Dial-on-Demand Routing (DDR) link.
Switch types refer to the ISDN software that runs on the switch, and not the manufacturer or the model.
This document uses static routing, and includes only the relevant and necessary commands. Either of the routers can initiate the connection, and all IP packets are "interesting," which means that the routers can dial, and can reset the DDR idle timer. No routing protocol is configured in this example, because routing updates can keep the link up indefinitely, and incur usage charges. This configuration helps you to connect a home or remote office where IP is the only protocol in use.
Network Diagram
This document uses this network setup:

Configurations
This document uses these configurations:
1.Remote Router

2.Main Router

Remote Router
hostname branch1
!
username main password secret1
!
isdn switch-type basic-dms100
!
interface Ethernet 0
ip address 131.108.64.190 255.255.255.0
!
interface BRI 0
encapsulation PPP
ip address 131.108.157.1 255.255.255.0
isdn spid1 415988488501 9884885
isdn spid2 415988488602 9884886
ppp authentication chap
dialer idle-timeout 300
dialer map IP 131.108.157.2 name main 4883
dialer-group 1
!
ip route 131.108.0.0 255.255.0.0 131.108.157.2
!
ip route 0.0.0.0 0.0.0.0 131.108.157.2
!
dialer-list 1 protocol ip permit


Main Router

hostname main
!
username branch1 password secret1
username branch2 password secret2
!
isdn switch-type basic-dms100
!
interface Ethernet 0
ip address 131.108.38.1 255.255.255.0
!
interface BRI 0
encapsulation PPP
ip address 131.108.157.2 255.255.255.0
isdn spid1 415988488201 9884882
isdn spid2 415988488302 9884883
ppp authentication chap
dialer idle-timeout 300
dialer map IP 131.108.157.1 name branch1 4885
dialer-group 1
!
ip route 131.108.64.0 255.255.255.0 131.108.157.1
!
Key Configuration Parameters
hostname name
The hostname of the router is used to identify the router to another router when it sends Challenge Handshake Authentication Protocol (CHAP) messages.
username name password secret
The username command is required to specify the CHAP secret message to use when challenged by another router. The two routers that need to communicate must share the same password.
isdn switch-type switch-type and isdn spid1 spid-number [ldn], isdn spid2 spid-number [ldn]
This router connects to a Northern Telecom DMS-100 switch. The Service Profile Identifiers (SPIDs) for the station are 415988488501 and 415988488602. These numbers were configured on the switch and will be given to a user by the local service provider. 9884885 and 9884886 are regular phone numbers for the two channels. They are normally called Local Directory Numbers (LDNs).
The isdn spid1 and isdn spid2 commands are not required for AT&T 5ESS switch software configured for point-to-point operation, but they are required for National ISDN-1 (NI1) software. Remember, switch types in this document refer to the ISDN software that runs on the switches, not the manufacturer or the model.
These are the only ISDN-specific commands required. The rest of the configuration is really dial-on-demand routing (DDR) configuration, and applies to other kinds of DDR interfaces, such as in-band and asynchronous.
Define Interesting Traffic
dialer-group group number
dialer-list dialer-group protocol protocol-name {permit deny}
dialer-list dialer-group protocol protocol-name list access-list-number
These commands are required to define "interesting" packet types. An interesting packet is one that activates the dialing sequence and resets the "idle-timeout" timer. In this example, all IP packets are interesting on one side, and an access list is used on the other side to demonstrate the two forms of the command. On branch1, all IP packets are interesting, but only non-Interior Gateway Routing Protocol (non-IGRP) packets are interesting on the main router.
ppp authentication chap
This command specifies that CHAP authentication must be used on this interface. See the explanation of the dialer map command for details.
dialer idle-timeout seconds
This command makes the router disconnect calls that have not had any interesting traffic for the configured time. Only outbound packets reset the idle timer.
dialer map protocol name remote-name broadcast speed 56 phone-number
The dialer map is used to distinguish between different remote sites, which can be connected at various times. A map is required for each site, and each protocol used. The remote name is the hostname of the other router. The broadcast flag specifies whether broadcast packets, such as routing updates, are sent for this protocol to this site. In this example, it is turned off.
The speed parameter defaults to 64. Set it to 56 in order to allow the call to complete successfully over networks that are not end-to-end ISDN. The phone number is used when calls are originated or authenticated in networks with calling number delivery. The number can be left out to create a "receive-only" dialer map. The example in this document shows a four-digit interoffice extension number, but a valid phone number of any length will work.
Dialer maps provide the network-layer-to-link-layer mapping required by the router to successfully encapsulate (or send packets out to) an interface. In this example, dialer maps include the phone number to call and the name of the other router. The name is essential to identify calling routers, through the use of CHAP. CHAP also provides some security, but is included in this basic configuration mainly because it allows identification of calling routers. In the general case, CHAP is required for identification of the calling router because calling number delivery is not always possible.
ip route network [mask] {address interface} [distance]
This command provides the static routing information necessary in order for the packets to be routed to the next hop appropriately. When packets are routed to a DDR interface, Demand is created, which, as the name implies, is an essential part of DDR.
Note: This is a simple configuration that you can use for IP traffic that uses static routing between two routers, which perform DDR over an ISDN interface. All unicast IP packets can trigger dialing, and will reset the idle timer. CHAP is used to identify the calling party router, and it is needed in the general case.
Verify
There is currently no verification procedure available for this configuration.
Troubleshoot
There is currently no specific troubleshooting information available for this configuration.
NetPro Discussion Forums - Featured Conversations Networking Professionals Connection is a forum for networking professionals to share questions, suggestions, and information about networking solutions, products, and technologies. The featured links are some of the most recent conversations available in this technology.

There are two ways to configure ISDN in a Cisco router. The first one is to setup the ISDN connection to be always on. This method will be very costly because most ISDN service providers charge not only by monthly subscription, but by the amount of data that you transfer. Having the connection opened 24/7, will cause extra expenses because all kinds of traffic will pass through the ISDN link.
The second method is Dial on Demand Routing (DDR). DDR employs a mechanism that filters the traffic into interesting (worth connecting for) and non-interesting (not worth it). Using the DDR the call scenario will be that the router does not setup the connection until “Interesting” traffic needs to be routed to the other side. Once the connection is setup, ALL kinds of traffic (interesting and non-interesting) will pass unless you filter the passing traffic with an access-list. Then, the router sets a down-counter (idle-timer), and if no interesting traffic comes in and the timer goes to zero, the connection is terminated. If interesting traffic comes in before the idle-timer is finished, the traffic is passed and the idle-timer is reset. What made this function possible is the very small call-setup time in ISDN.
If you are connecting two nodes using ISDN, keep reading. However if you are connecting more than two nodes, you will need to refer to this procedure for configuring DDR Dialer Profiles.
Configuring Dial-on-Demand-Routing ISDN:
1. The first thing to do is to setup routing. Static routing is usually preferred with DDR. Setting dynamic routing protocol, will cause the link to be on all (or most) of the time. Thus, static routing is a better solution. You can setup dynamic routing and tune it a bit for the DDR. This tuning might include changing the timers of routing updates.
I will give an example of static routing;
Router(config)#ip route 192.168.1.0 255.255.255.0 192.168.2.1
Router(config)#ip route 192.168.2.1 255.255.255.255 bri0
Or, a default route,
Router(config)#ip route 0.0.0.0 0.0.0.0 bri0
Remember that you need to setup routing on both ends of the WAN link.
2. Specify the type of the ISDN switch. This piece of information should be provided to you by the ISDN service provider. You can issue this command,
Router(config)#isdn switch-type SSSSS
where SSSSS is the ISDN switch type. Issuing this command in the global configuration mode will cause ALL your ISDN interfaces to be set to use this type of switch. You can set different types of switches for different interfaces if you issue the command in the interface configuration mode like the following example:
Router(config)#int bri0
Router(config-if)#isdn switch-type SSSS1
Router(config-if)#int bri1
Router(config-if)#isdn switch-type SSSS2
After defining the switch type, identify the SPIDs in the BRI interface configuration mode,
Router(config-if)#isdn spid1 XXXXXXX YYY
Router(config-if)#isdn spid2 XXXXXXX YYY
The numbers used here should be provided to you by the ISDN service provider. Most providers in Europe do not use SPIDs in their ISDN networks. So, unless you are supplied with SPID numbers from the provider, just neglect all the commands of setting SPIDs in this procedure.
3. Specify interesting traffic to the router. This traffic is defined as the traffic permitted by a command named ‘dialer-list’ as a similar to ‘access-list’.
This can be done in two ways; the first is to use the following command,
Router(config)#dialer-list X protocol YY permit
where X is the dialer-list number and YY is the protocol you want to permit. And you can use ‘deny’ instead of the ‘permit’ part. This is not a very powerful way of defining the interesting traffic. Thus, I recommend the second way. The second way is to do a complete access-list permitting the traffic that we want the router to consider interesting, and then attach it to a dialer-list.
We create the access-list the exact same way we create any other access-list, but we do not apply it to an interface, but instead, we associate it with a dialer-list. All the traffic permitted by this access-list, will be considered interesting. An example is the following:
Router(config)#access-list YYY deny tcp any any telnet
Router(config)#access-list YYY deny icmp any any
Router(config)#access-list YYY permit ip any any
And the step that will associate the access-list to the dialer-list is:
Router(config)#dialer-list X protocol ip list YYY
where X is the dialer-list number and YYY is the access-list number. These two numbers do not need to be the same.
Please remember that this dialer-list and access-list does NOT filter the traffic outgoing through the ISDN interface, it just chooses which traffic is entitled to initiate a call. Once the call is setup, ALL traffic willing to pass through the ISDN link will pass. If you want to filter the traffic that is passing through the ISDN interface, create another access-list for that with the filters that you find appropriate and apply it to the BRI or PRI interface as you do to any other type of interface.
4. Setup the encapsulation protocol, PPP. Using PAP authentication does not provide that much of security, so we will use CHAP for authentication.
The first thing to do to configure PPP to use CHAP is to set a username and a password.
Router(config)#username USER password PASS
where USER is the username and PASS is the password. The username should be the hostname of the other end and the password is the secret password of the other end. If you like to use different usernames and passwords, please refer to the PPP configuration procedure .
Then, move into the interface configuration mode of the ISDN interface,
Router(config)#int bri X/X
Now, set an IP address and a subnet mask for the interface,
Router(config-if)#ip address XXX.XXX.XXX.XXX YYY.YYY.YYY.YYY
Set the encapsulation and authentication types;
Router(config-if)#encapsulation ppp
Router(config-if)#ppp authentication chap
5. Apply the dialer-list to the interface,
Router(config-if)#dialer-group X
where X is the dialer-list that was setup in step 3.
6. Define the idle-timeout that you find appropriate for each call,
Router(config-if)#dialer idle-timeout ZZZ
where ZZZ is the duration of the call in seconds (default is usually 120 seconds). The idle-timeout is the period of time in which the call will remain unterminated waiting for more interesting traffic. If more interesting traffic comes in before the timer is over, the timers will be reset. If no interesting traffic comes in, the call will be terminated even if there was non-interesting traffic being transferred.
7. If you are using this link between to points only and your router will be dialing only one destination using the ISDN network, use the following command to set the dialer string:
Router(config-if)#dialer string XXXXX
where XXXXX is the dialer string that is provided to you by the service provider. This dialer string is similar to the phone number that you dial in the regular PSTN. So, you command the router to dial the string of the other side not your side.
For further security, you can use a different command that associates the dialing to a destination IP address with a username and a dialer string,
Router(config-if)#dialer map ip YYY.YYY.YYY.YYY name USER XXXXX
where YYY.YYY.YYY.YYY is the IP address of the other end of the ISDN link
USER is the same username that you have setup to use with PPP
XXXXX is the dialer string of the other end of the ISDN link.
8. You can optionally use the following command to set up a threshold of load on which the second channel (in a BRI link) becomes active.
Router(config-if)#dialer load-threshold VVV either
where VVV is a number between 1 and 255, 1 being the minimum load and 255 being %100 load on the first channel. This means that this command tells the router to activate the second channel once the first one is VVV/255 loaded.
9. You can check the operation of the ISDN using the following commands;
Router#show isdn active
Router#show isdn status
Router#show dialer
and
Router#debug isdn q921
Router#debug isdn q931
Router#debug dialer