Hardware Secrets explains how Gigabit Ethernet works
Gigabit Ethernet allows network transfers up to 1.000 Mbps using standard Cat 5 UTP (unshielded twisted pair) cabling. How can this be accomplished, since Cat 5 cables can run only up to 100 Mbps? We will explain this and also other very interesting issues regarding Gigabit Ethernet performance.How Gigabit Ethernet Works