[2] In the original 10BASE5 and 10BASE2 Ethernet varieties, a segment would therefore correspond to a single coax cable and all devices tapped into it.
At this point in the evolution of Ethernet, multiple network segments could be connected with repeaters (in accordance with the 5-4-3 rule for 10 Mbit Ethernet) to form a larger collision domain.
This corresponds to the extent of an OSI layer 1 network and is equivalent to the collision domain.
Traffic within a layer-2 segment can be separated into virtually distinct partitions by using VLANs.
Hosts on a subnet communicate directly using the layer-2 segment that connects them.