Computer networks, ethernet technologies, mạng máy tính, công nghệ ethernet
2008/7/19 1 Module 7: Ethernet Technologies 2008/7/19 2 Outline 10-Mbps and 100-Mbps Ethernet 10-Mbps Ethernet 10BASE5 10BASE2 10BASE-T 10BASE-T wiring and architecture 100-Mbps Ethernet 100BASE-TX 100BASE-FX Fast Ethernet architecture Gigabit and 10-Gigabit Ethernet 1000-Mbps Ethernet 1000BASE-T 1000BASE-SX and LX Gigabit Ethernet architecture 10-Gigabit Ethernet 10-Gigabit Ethernet architectures Future of Ethernet 2008/7/19 3 7.1 10-Mbps and 100-Mbps Ethernet 2008/7/19 4 10-Mbps Ethernet Legacy Ethernet : 10BASE5, 10BASE2, and 10BASE-T Ethernet. The four common features of Legacy Ethernet : The same timing parameters The same frame format 2008/7/19 5 10-Mbps Ethernet (cont.) The four common features of Legacy Ethernet (cont.) : The same transmission process SQE (signal quality error), it is always used in half-duplex. SQE can be used in full-duplex operation but is not required. Manchester line encoding Falling edge > bit 0 Raising edge > bit 1 The same basic design rule The timing limits Cable length and its propagation delay Delay of repeaters Delay of transceivers Interframe gap shrinkage ( 減低) Delays within the station 5-4-3 rule No more than 5 segments No more than 4 repeators No more than 3 populated segments between any two distant stations.(只有三個 segments 可接電腦） 2008/7/19 6 5-4-3 rule 2008/7/19 7 10BASE5 A single thick coaxial cable bus. 10BASE5 is the first medium used for Ethernet. Manchester encoding The primary benefit of 10BASE5 was length. Each of the maximum five segments of thick coax may be up to 500 m (1640.4 ft) in length. The cable is large, heavy, and difficult to install. 2008/7/19 8 10BASE2 Manchester encoding The cable is smaller, lighter, and easier to install than 10BASE5. BNC connectors / T-shaped connector 2008/7/19 9 10BASE-T Manchester encoding Category 3 / Category 5e RJ-45 2008/7/19 10 10BASE-T wiring and architecture