Command
PPP Authentication PAP
Use
This command is used to authenticate a link using PAP.
Syntax
Router(config-if)#ppp authentication pap
Example
In this example, R1’s S1/1 interface is configured to authenticate R3 using PAP.
R1(config)#int s1/1 R1(config-if)#encapsulation ppp R1(config-if)#ppp authentication pap R1(config-if)# *Mar 2 01:42:38.237: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/1, changed state to down R1(config-if)#exit R1(config)#username R3 password cisco
Here we can see that the link now requires authentication.
R3(config)#int s1/1 R3(config-if)#do debug ppp authe PPP authentication debugging is on R3(config-if)#shut R3(config-if)# *Mar 2 02:40:26.045: %LINK-5-CHANGED: Interface Serial1/1, changed state to administratively down *Mar 2 02:40:27.045: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/1, changed state to down R3(config-if)#no shut R3(config-if)# *Mar 2 02:40:31.001: %LINK-3-UPDOWN: Interface Serial1/1, changed state to up R3(config-if)# *Mar 2 02:40:31.009: Se1/1 PPP: Using default call direction *Mar 2 02:40:31.013: Se1/1 PPP: Treating connection as a dedicated line *Mar 2 02:40:31.013: Se1/1 PPP: Session handle[C000001C] Session id[29] *Mar 2 02:40:31.017: Se1/1 PPP: Authorization required *Mar 2 02:40:31.237: Se1/1 PPP: Authorization required R3(config-if)# *Mar 2 02:40:33.117: Se1/1 PPP: Authorization required R3(config-if)# *Mar 2 02:40:35.153: Se1/1 PPP: Authorization required *Mar 2 02:40:37.153: Se1/1 PPP: Authorization required *Mar 2 02:40:39.173: Se1/1 PPP: Authorization required R3(config-if)#do un all All possible debugging has been turned off
After we provide the configured username and password the link comes up.
R3(config)#int s1/1 R3(config-if)#ppp pap sent-username R3 password cisco R3(config-if)# *Mar 2 02:40:54.165: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/1, changed state to up