network was one large collision domain and one large broadcast domain,
whereas layer 2 switches break up collision domains on each port, but all
ports are still considered, by default, to be in one large broadcast domain.
Only virtual LANs, covered in Chapter 3, break up broadcast domains in a
layer 2 switched network.
Ethernet, you can theoretically double the throughput on each link. In the
next sections, we'll discuss how Ethernet is used in your internetwork, the
differences between the Ethernet types, and half- and full-duplex.
Ethernet types:
twisted-pair. This Ethernet technology has the highest install base of any net-
work in the world. It runs the Carrier Sense Multiple Access/Collision Detec-
tion (CSMA/CD) protocol and, if correctly installed, is an efficient network.
However, if it gets too large and the network is not segmented correctly,
problems occur. It is important to understand collision and broadcast
domains and how to correctly design the network with switches and routers.
FastEthernet (100BaseT) is quickly replacing it as the prices for 100BaseT
continue to drop. It would be poor design to place 10BaseT at the distribu-
tion or core layers. You need transits that are much faster than 10BaseT at
these layers.