思科第一册第九章（CISCO, Volume 1, ninth）.docVIP

思科第一册第九章（CISCO, Volume 1, ninth） The difference between the standard Ethernet, fast Ethernet, Gigabit Ethernet and Gigabit Ethernet is usually called Ethernet physical layer, PHY. Comply with the IEEE standard 802.3 ethernet. Now through the cable and twisted pair cable operation defines four data rate: 10 - Mbps 10Base-T Ethernet 100 - Mbps Fast Ethernet 1000 - Gigabit Ethernet Mbps 10 - Gigabit Ethernet Gbps Although these different data rate will achieve many different Ethernet, but here only introduce more commonly used Ethernet implementation method. The picture shows some features of Ethernet PHY. This section will discuss the Ethernet physical layer operation of the first part, starting from 10Base-T, and then discuss the variant 10 Gbps. 10 Mbps Ethernet mainly include: The use of coaxial cable diameter 10BASE5 The use of coaxial thinnet 10BASE2 The use of 3 kinds of /5 unshielded twisted pair cable 10BASE-T Early 10BASE5 and 10BASE2 using Ethernet Coaxial Cable in the physical bus. The method is no longer used nowadays, the new 802.3 standard will no longer support them. 10 - 10BASE-T Mbps Ethernet 10BASE-T uses Manchester encoding, through two UTP cable transmission. The early use of 10BASE-T 3 cable. Cable but now generally use 5 or higher specification. 10 Mbps Ethernet is considered traditional Ethernet, using physical star topology. Ethernet link length of 10BASE-T do not need a hub or repeater within 100 meters. Two of the cable four line with 10BASE-T, and in each terminal with 8 pin RJ-45 connector terminal. Connected to pins 1 and 2 on the line for transmitting, connected to pins 3 and 6 on the line for receiving. The picture shows for 10BASE-T Ethernet RJ45 pin. The new LAN generally do not choose 10BASE-T. But there are still many Ethernet 10BASE-T. The hub in the 10BASE-T network to replace the switch, greatly increase the throughput of the network, prolong the life of traditional ethernet. Connect to the 10BASE-T link switch supports half duple