PPP addresses the problems of Internet connectivity by
employing three
main components:
- A method for encapsulating datagrams over serial links. PPP uses
High-Level Data Link Control (HDLC) as a basis for encapsulating
datagrams over point-to-point links.
- A Link Control Protocol (LCP) for
establishing, configuring, and testing the data-link connection.
- A family of Network Control
Protocols (NCPs) for establishing and configuring different
network-layer protocols. PPP is designed to allow the simultaneous use
of multiple network-layer protocols. Today, PPP supports other protocols besides IP, including Internetwork Packet Exchange (IPX) and Appletalk. As shown in the Figure, PPP uses its NCP component to encapsulate multiple protocols.
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