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New Member

PPP questions

When setting up PPP on a serial int . Does it matter in what order your type the config for it. For example

interface Serial0/0/0

description Link to Home office

ip address

encapsulation ppp

ppp authentication chap

clock rate 9600

username R2 password Bob

Also is PPP only for serial interfaces ?

  • WAN Routing and Switching

PPP questions

Well I don't believe you can just go to an ethernet interface and type 'encapsulation ppp'. That would be just for serial interfaces, but you can run ppp over ethernet, which is called PPPoE. PPPoE can be configured as a point to point

connection between two different ethernet ports. It basically encapsulates ppp inside of an ethernet frame.

New Member

PPP questions

Ok so when typing it in the CLI do I have to type it in a certain order for it work correctly ?

F.e username bob password cisco

encap ppp

ppp authen chap etc.....

PPP questions

That should help you out some.

Cisco Employee

PPP questions

Hello James,

John is right. You can directly configure PPP encapsulation only on serial and ISDN interfaces. While PPP can also be used on Ethernet, Frame Relay, ATM or Packet-over-SONET interfaces, these deployments are more complex and for simplicity, I suggest not taking them into consideration now.

Regarding the order of configuration commands, the only rule is to issue the encapsulation ppp before entering PPP-specific commands like ppp authentication, ppp pap, ppp chap, etc. Otherwise, the order does not matter.

Your configuration has a small inaccuracy - the username command would not be placed into the interface configuration but rather in the global configuration level, even if you issue that command in interface configuration mode.

Best regards,


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