Lab 5.8.1: ISDN PRI CALL

Objectives:

  • Place an ISDN BRI to ISDN PRI call from the branch offices to the central site.

Scenario:

Given a Central site Cisco-IOS router with ISDN PRI capability and branch office site Cisco-IOS routers with ISDN BRI capability, configure all routers so that you can place an ISDN call between your three company sites.

Notes: 

Lab Tasks:

  1. Cable the lab as shown in the diagram. Paste your BRI to BRI configs into Phoenix and Denver.
  2. The first router to be configured will be the Central office router. Log into the Central office router and enter global configuration mode.
  3. Configure the following basic information into the router:
  • Configure the hostname Central on the router.
  • Configure the router to prevent the lookup of misspelled words.

What is the command to prevent the lookup of misspelled words?

  • Configure the enable password to be cisco.
  • Configure the FastEthernet 0/0 interface with the IP address 172.16.0.1/24.
  • Configure the line VTY 0 4 to request a login with the cisco password.
  1. Now it is time to configure the ISDN PRI connection! The first step will be to specify the ISDN switch type that is specified by the Phone Company. In this lab, the switch type will be National. The command to configure the switch type is:

    Central(config)#isdn switch-type primary-ni
  2. The next step will be to configure the hostname to ip mapping and the username and passwords. Continue using cisco as the password. The commands to do this are:

    Central(config)#ip host phoenix 192.168.2.1
    Central(config)#ip host denver 192.168.3.1
    Central(config)#username phoenix password cisco
    Central(config)#username denver password cisco

  3. Specify what types of traffic will generate a call to the remote router. Traffic that generates a call to another router is called "interesting traffic." In this lab, any IP traffic is considered "interesting" and should generate a call. Configure a dialer-list to specify IP traffic as interesting with the following command:

    Central(config)#dialer-list 1 protocol ip permit
  4. The Central office router must have a route to both the Phoenix and Denver sites. Configure two static routes to the LAN interfaces of these routers.

    What are the commands to do this?


  5. The PRI controller card must be configured to use extended super frame, the binary 8-zero substitution linecode, and set to use all timeslots. To configure the PRI controller issue the following commands:

    Central(config)#controller t1 1/0
    Central(config-controller)#framing esf
    Central(config-controller)#linecode b8zs
    Central(config-controller)#pri-group timeslots 1-24

  6. The final part of the configuration is to configure the PRI serial interface. Go to the PRI interface and configure the IP address, Dialer-group number, PPP encapsulation, PPP multilink, and CHAP authentication. The commands to do this are:

    Central(config)#interface serial 1/0:23
    Central(config-if)#ip address 10.1.1.1 255.255.255.0
    Central(config-if)#dialer-group 1
    Central(config-if)#dialer load-threshold 1 outbound
    Central(config-if)#encapsulation ppp
    Central(config-if)#ppp multilink
    Central(config-if)#ppp authentication chap

  7. Since this is an ISDN connection, there is an hourly/minute charge. For that reason, one probably does not want the circuit to be up while there is no traffic. In other words, this line should be used on an "As needed" basis. To enforce this behavior, the router needs to be told when to hang up. In this lab, if the link is idle for 60 seconds, the router should teardown the call. The command to enforce the timeout policy is as follows:

    Central(config-if)#dialer idle-timeout 60
  8. Lastly, the router needs to know what numbers to dial, next hop IP address, and name to log in with. To configure the dialer-map, issue the following command:

    Central(config-if)#dialer map ip 10.1.1.2 name Phoenix 5551234
    Central(config-if)dialer map ip 10.1.1.3 name Denver 5554000

  9. Issue the following commands to check the status of the ISDN interface and connection:

    Central#show isdn status
    Central#debug isdn q921

    Document your findings from each command below:


  10. Save your configuration. It is now time to configure the Phoenix Router.
  11. The first step will be to configure the hostname to ip mapping the username and password of the router to be dialed into, and a static route to the central office LAN. Continue using cisco as the password. The commands to do this are:

    Phoenix(config)#ip host central 172.16.0.1
    Phoenix(config)#username central password cisco
    Phoenix(config)#ip route 172.16.0.0 255.255.0.0 10.1.1.1

  12. The final part of the configuration is to configure the BRI interface. Go to the BRI 0/0 interface and configure the dialer map command. The commands to do this are:

    Phoenix(config)#interface bri 0/0
    Phoenix(config-if)#dialer map ip 10.1.1.1 name central 5555000

  13. Save your configuration. It is now time to configure the Denver Router.
  14. The first step will be to configure the hostname to ip mapping, the username and password of the router to be dialed into, and a static route to the central office LAN. Continue using cisco as the password. The commands to do this are:

    Denver(config)#ip host central 172.16.0.1
    Denver(config)#username central password cisco
    Denver(config)#ip route 172.16.0.0 255.255.0.0 10.1.1.1

  15. The final part of the configuration is to configure the BRI interface. Go to the BRI 0/0 interface and configure the dialer map command. The commands to do this are:

    Denver(config)#interface bri 0/0
    Denver(config-if)#dialer map ip 10.1.1.1 name central 5555000

  16. Save your configuration.
  17. From the Phoenix router issue the following commands:

Phoenix#debug dialer
Phoenix#ping central

Document your findings below: