What are SLIP, CSLIP and PPP?
SLIP stands for Serial Line Internet Protocol. SLIP was a “non-standard” for framing IP packets and shipping them over a serial line (e.g. a cable, or a pair of modems), thus allowing a home machine to dial up and become part of the Internet. Effectively, SLIP turned a serial port into a logical Ethernet port. PPP (see below) has effectively replaced SLIP as the standard of choice for Internet connections.