2.3 Gigabit Ethernet
2.3.1 Specifications

Another higher-bandwidth technology became available in June 1998. Gigabit Ethernet (IEEE standard 802.3z) specifies operations at 1000 Mbps, another tenfold bandwidth improvement. It was discussed earlier how stations are hard-pressed to fully utilize 100-Mbps Ethernet. Why then do we need a gigabit-bandwidth technology? Gigabit Ethernet proponents expect to find it as either a backbone technology or as a pipe into very-high-speed file servers. This contrasts with Fast Ethernet in that network administrators can deploy Fast Ethernet to clients or servers, or use it as a backbone technology.

In a switched network, Gigabit Ethernet interconnects switches to form a high-speed backbone. The switches in the figure have low-speed stations connecting to them (10 and 100 Mbps), but have 1000-Mbps to pass traffic between workstations. A file server in the network also benefits from a 1000-Mbps connection supporting more concurrent client accesses.