Gigabit Ethernet is available for copper and fibre optic interfaces. It further increases the speed of the Ethernet protocol, offering a tenfold speed increase over Fast Ethernet to 1 gigabit per second (Gbps).
10G transmssion is supported over fibre. The 10GBaseT Ethernet specification allows 10Gbps transmission over UTP over shorter distances (upto 55m) )using CAT6 cable at a symbol rate of 3,200 000 000 Symbols/sec. Each CAT6 twisted pair operates at 10 Gbps (128 DSQ coded with LDPC coding). The use of a screened CAT6a cable allows transmission upto 100m.
The IEEE 802.3bq standard specifies 40 Gbps over CAT7a copper UTP. This uses four twisted pairs to transmit up to 30m distance. Each pair operates at 10 Gbps. This shorter distance targets data centre applications, rather than home/enterprise applications.
For more information see:
Unshielded Twisted Pair (UTP) cabling