All WAN links inside the ABC University network use PPP with CHAP for authentication security.
Which command will display the CHAP authentication process as it occurs between two routers in
the network?

A.
show ppp authentication chap

B.
show interface serial0

C.
debug PPP authentication

D.
show CHAP authentication

E.
debug CHAP authentication

Explanation:
Whenever you’re asked to display a process in real time, you must use a debug command as
show commands do not display anything in real time. Debug PPP authentication will display the
authentication process of a PPP line, including the CHAP process.
Reference: CCNA Self-Study CCNA ICND exam certification Guide (Cisco Press, ISBN 1-58720-
083-X) Page 314.