Point-to-Point Protocol (PPP) and Serial Line IP (SLIP) are widely used
protocols for carrying IP packets over a serial link. A number of institutions
offer dialup PPP and SLIP access to machines that are on the Internet, thus
providing IP connectivity to private persons (something that's otherwise
hardly affordable).
No hardware modifications are necessary to run PPP or SLIP; you can use
any serial port. Since serial port configuration is not specific to
TCP/IP networking, we have devoted a separate chapter to this. Please
refer to Chapter 4, for more information. We cover
PPP in detail in Chapter 8, and SLIP in
Chapter 7.
