Lab 7. Configuring PPP Encapsulation
CCNA 200–301
Lab Objective:
The objective of this lab exercise is to enable PPP encapsulation on Cisco router Serial interfaces and verify the state of the PPPencapsulated interfaces. This lab also covers debugging PPP links to see the different states of PPP negotiation
Lab Purpose:
PPP configuration and verification is a fundamental skill. PPP is one of the most popular Layer 2 protocols used on WANs. As a Cisco engineer, as well as in the Cisco CCNA exam, you will be expected to know how to configure and verify PPP encapsulation.
Lab Topology:
Please use the following topology to complete this lab exercise:
Task 1:
Configure hostnames on R1 and R2 as illustrated in the topology.
Task 2:
Enable Serial interfaces on R1 and R2. The Serial0/1/0 interface on R2 is identified as the DCE in the topology. Use the appropriate show command to verify that this interface is indeed the DCE. Configure the DCE interface on R2 to provide clocking to R1. The clock speed should be 250 Kbps. Verify that R1 receives clocking information from R2.
Task 3:
Enable PPP encapsulation on R1 and R2 Seriaol0/0 interfaces. Configure IP addressing on R1 and R2 Serial0/0 interfaces as illustrated in the topology. Verify your interface encapsulation, which should now be PPP. Test connectivity between R1 and R2 by pinging between the routers over the PPP link.
Task 4:
Enable PPP link negotiation debugging on R1. Next, issue the shutdown command, followed by the no shutdown command on Serial0/0. As the interface goes down and comes back up, you should see the different phases of PPP link negotiation. Disable debugging when you are done.
Task 1:
For reference information on configuring hostnames, please refer to earlier labs.
Task 2:
For reference information on verifying DTE/DCE status, please refer to earlier labs.
Task 3:
R1#conf t
R1(config)#int s0/1/0
R1(config-if)#encapsulation ppp
R1(config-if)#ip address 10.0.254.1 255.255.255.240
R1(config-if)#no shut
R2#conf t
R2(config)#interface s0/1/0
R2(config-if)#encapsulation ppp
R2(config-if)#ip add 10.0.254.2 255.255.255.240
R2(config-if)#no shut
R2(config-if)#end
R1#show interfaces s0/1/0
R1#ping 10.0.254.2
Task 4:
R1#debug ppp negotiation
R1#conf ter
R1(config)#int s0/1/0
R1(config-if)#shut
R1(config-if)#no shut
R1(config-if)#end
R1#undebug all
