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The TCP/IP Guide  9  TCP/IP Lower-Layer (Interface, Internet and Transport) Protocols (OSI Layers 2, 3 and 4)       9  TCP/IP Network Interface Layer (OSI Data Link Layer) Protocols

TCP/IP Network Interface Layer (OSI Data Link Layer) Protocols 1 SLIP and PPP Overview and Role In TCP/IP

The TCP/IP protocol suite is structured around the Internet Protocol (IP). IP operates at layer three of the OSI Reference Model, and assumes that it will be layered on top of an existing layer two technology. However, certain types of connections exist that do not include a layer two protocol over which IP can run. To enable TCP/IP to operate on these kinds of links, two special TCP/IP data link layer protocols have been created.

In this section I describe the protocols used specifically to implement data link layer connectivity for TCP/IP internetworks. I begin with a brief overview of the two protocols used to connect devices at layer two and how they fit into the TCP/IP protocol suite as a whole. I then have a single topic that describes the operation of the rather simple Serial Line Internet Protocol (SLIP), and a comprehensive section on the much more capable Point-to-Point Protocol (PPP).

TCP/IP Network Interface Layer (OSI Data Link Layer) Protocols 1 SLIP and PPP Overview and Role In TCP/IP