Ethernet (CSMA/ CD)
developed by Xerox early 70's
- commercialized mid/late 70's
- de facto standard taken up and generalized as dejure standard IEEE 802.3
physical medium
- baseband coax (thick and thin)
- twisted pair (recent introduction)
length restrictions - thicknet:
- 500m max distance between repeaters
- up to 4 repeaters - 2.5 max length
- restriction due to maximum limit of round-trip propagation delay of 51.2 _s