The Parallel Line Internet Protocol (PLIP) is very similar to SLIP, but works at higher speeds via a parallel port and null-printer cable.
For most uses PLIP has been replaced by increasingly-common Ethernet protocol based networking support and cross-cable setups –– or other point-to-point connections such as an USB host-to-host brige/cable –– used to transfer files between two computers where a network is not necessary or available.