switches in each building to the core switches.
effectively connect your high-performance servers to the network with
gigabit speeds. However, remember that, unless the server is tremen-
dously fast, you might not notice a difference in speeds from FastEthernet
because the server processing can become the bottleneck. Time to throw
out your Pentium 90 servers.
The standard was called 802.3z. Gigabit uses Ethernet framing the same way
10BaseT and FastEthernet does. This means that, not only is it fast, it can run
on the same network as older Ethernet technology, which provides a nice
migration plan. The goal of the IEEE 802.3z was to maintain compatibility
to the 10Mb/s and 100Mb/s existing Ethernet network. They needed to pro-
vide a seamless operation to forward frames between segments running at
different speeds. The committee kept the minimum and maximum frame
lengths the same. However, they needed to change the CSMA/CD for half-
duplex operation from its 512-bit times to help the distance that Gigabit
Ethernet could run.
Gigabit is run to the desktop, however, it's hard to imagine what we'll need
to run the backbone with. 1000BaseT to the rescue! Yes, 10 Gigabit Ethernet
is just around the corner!
net. FastEthernet uses the Media Independent Interface (MII), and Gigabit
uses the Gigabit Media Independent Interface (GMII). 10BaseT used the
Attachment Unit Interface, or AUI. A new interface was designed to help
FastEthernet scale to 100Mbps, and this interface was redesigned for Gigabit
Ethernet. The GMII uses an 8-bit data path instead of the 4-bit path that
FastEthernet MII uses. The clocking must operate at 125MHz to achieve the
1Gb/s data rate.