[2] A router based on the PDP-11 computer from Digital Equipment Corporation with software from MIT was used to connect the Ethernet to the ARPANET.
[3] The PARC Universal Packet protocol was initially used on the local parts of the network, which was the experimental version of Ethernet with a data rate under 3 megabits/second.
As the TCP/IP protocols evolved through the 1980s, a TCP/IP network was built on the main campus, extending to other departments, and connecting many other computers.
It was inspired by the Alto, but used a more modular design powered by a Motorola 68000 processor interfaced to other circuit boards using Multibus.
[5] The original router software was called NOS, Network Operating System, written by William Yeager, a staff research engineer at Stanford's medical school.