Datasheet

Lab – Configuring Basic PPP with Authentication

Jun 20 03:02:02.017: Se0/0/0 PPP: O pkt type 0x0021, datagramsize 68

Jun 20 03:02:02.897: Se0/0/0 PPP: I pkt type 0x0021, datagramsize 112 link[ip]

Jun 20 03:02:03.561: Se0/0/0 PPP: O pkt type 0x0021, datagramsize 80

From the debug message, what phases does PPP go through when the other end of the serial link on the

Central router is configured with PPP encapsulation?

____________________________________________________________________________________

PPP goes through the following phases: DOWN, ESTABLISHING, and UP.

What happens when PPP encapsulation is configured on each end of the serial link?

____________________________________________________________________________________

The link comes up, and the OSPF adjacency is restored.

i. Issue the undebug all (or u all) command on the Branch1 and Central routers to turn off all debugging on

both routers.

j. Issue the show ip interface brief command on the Branch1 and Central routers after the network

converges. What is the status for interface S0/0/0 on both routers?

____________________________________________________________________________________

Serial 0/0/0 has status up and protocol up.

Branch1# show ip interface brief

Interface IP-Address OK? Method Status Protocol

Embedded-Service-Engine0/0 unassigned YES unset administratively down down

GigabitEthernet0/0 unassigned YES unset administratively down down

GigabitEthernet0/1 192.168.1.1 YES manual up up

Serial0/0/0 10.1.1.1 YES manual up up

Serial0/0/1 unassigned YES unset administratively down down

Central# show ip interface brief

Interface IP-Address OK? Method Status Protocol

Embedded-Service-Engine0/0 unassigned YES unset administratively down down

GigabitEthernet0/0 unassigned YES unset administratively down down

GigabitEthernet0/1 unassigned YES unset administratively down down

Serial0/0/0 10.1.1.2 YES manual up up

Serial0/0/1 10.2.2.2 YES manual up up

Loopback0 209.165.200.225 YES manual up up

k. Verify that the interface S0/0/0 on both Branch1 and Central routers are configured for PPP

encapsulation.

Record the command to verify the PPP encapsulation in the space provided below.

____________________________________________________________________________________

Branch1# show interfaces s0/0/0

Central# show interfaces s0/0/0

l. Change the serial encapsulation for the link between the Central and Branch3 routers to PPP

encapsulation.

Central(config)# interface s0/0/1