RFC 1661 -The Point-to-Point Protocol (PPP) specifies that the Point-to-Point Protocol (PPP) provides a standard method for transporting multi-protocol datagrams over point-to-point links. PPP is comprised of three main components:
1 A method for encapsulating multi-protocol datagrams. 2 A Link Control Protocol (LCP) for establishing, configuring, and testing the data-link connection. 3 A family of Network Control Protocols (NCPs) for establishing and configuring different network-layer protocols.