CISCO CCNA Exam – Q325

Which PPP subprotocol negotiates authentication options?

A. NCP
B. ISDN
C. SLIP
D. LCP
E. DLCI

Correct Answer: D

Explanation:
The PPP Link Control Protocol (LCP) is documented in RFC 1661. LPC negotiates link and PPP parameters to dynamically configure the data link layer of a PPP connection.
Common LCP options include the PPP MRU, the authentication protocol, compression of PPP header fields, callback, and multilink options.