Gigabit Ethernet
Fast Ethernet can be scaled by an added adjustment of consequence with the use of Gigabit Ethernet
(which supports 1,000 Mbps or 1 Gbps) application the aforementioned IEEE 802.3 Ethernet anatomy architecture as
before. This scalability allows arrangement designers and managers to advantage absolute knowledge
and technologies to install, migrate, manage, and advance Gigabit Ethernet networks.
However, the concrete band has been adapted to admission abstracts manual speeds. Two
technologies were alloyed calm to accretion the allowances of each: The IEEE 802.3 Ethernet
standard and the American National Standards Institute (ANSI) X3T11 FibreChannel. IEEE
802.3 provided the foundation of anatomy format, CSMA/CD, abounding duplex, and other
characteristics of Ethernet. FibreChannel provided a abject of accelerated ASICs, optical
components, and encoding/decoding and serialization mechanisms. The consistent agreement is
termed IEEE 802.3z Gigabit Ethernet.
Gigabit Ethernet supports several cabling types, referred to as 1000BaseX. Table 3-4 lists the
cabling blueprint for anniversary type.
In a campus network, Gigabit Ethernet can be acclimated in the about-face block, the amount block, and in
the server block. In the about-face block, it is acclimated to affix admission band switches to distribution
layer switches. In the core, it connects the administration band to the amount switches, and also
interconnects the amount devices. For a server block, a Gigabit Ethernet about-face in the server block
can accommodate accelerated access to alone servers.
74 Chapter 3: Basic About-face and Port Configuration
Finally, Cisco has continued the abstraction of Fast EtherChannel to array several Gigabit
Ethernet links to act as a distinct concrete connection. Gigabit EtherChannel (GEC) allows
two to eight full-duplex Gigabit Ethernet access to be aggregated, for up to 16 Gbps
throughput. Port accession and the EtherChannel technology are declared added in
Chapter 5.
NOTE The Gigabit Ethernet Alliance offers added account about Gigabit Ethernet, and its operation,
migration, and standards. Refer to the web site: www.gigabit-ethernet.org