PPP overview
Point-to-Point Protocol (PPP) is a link layer protocol that carries network layer packets over point-to-point links. 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—Provide network security. Protocols include Password Authentication Protocol (PAP), Challenge Handshake Authentication Protocol (CHAP), Microsoft CHAP (MS-CHAP), and Microsoft CHAP Version 2 (MS-CHAP-V2).