PPP overview
Point-to-Point Protocol (PPP) is a point-to-point link layer protocol. It provides user authentication, supports synchronous/asynchronous communication, and allows for easy extension.
PPP includes the following protocols:
Link control protocol (LCP)—Establishes, tears down, and monitors data links.
Network control protocol (NCP)—Negotiates the packet format and type for data links.
Authentication protocols—Authenticate users. Protocols include the following:
Password Authentication Protocol (PAP).
Challenge Handshake Authentication Protocol (CHAP).
Microsoft CHAP (MS-CHAP).
Microsoft CHAP Version 2 (MS-CHAP-V2).