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Gigabit Ethernet. Freeha Khan Is 8040 Data Communication Theory and Practice. Ethernet History. Ethernet has evolved from a 4800bps contention based radio channel transmission system to he most popular local area networking standard
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Gigabit Ethernet Freeha Khan Is 8040 Data Communication Theory and Practice
Ethernet History • Ethernet has evolved from a 4800bps contention based radio channel transmission system to he most popular local area networking standard • The idea of shared data transmission channel began in 1960s by Norman Abramson at University of Hawaii • Today’s Ethernet started in 1972 by Bob Metcalfe at Xerox research center - PARC
Ethernet Evolution • Initially, the most commonly installed Ethernet systems were called 10BASE-T, which gave way to 100BASE-T, also known as fast Ethernet, which could (theoretically) transmit at 100 mbps • Fast Ethernet now giving up its place at the backbone to Gigabit Ethernet which can (theoretically) provide a bandwidth of a billion bits per second
Ethernet Evolution • Evolution and comparison
Gigabit Ethernet • In 1996, twenty eight companies formed the Gigabit Ethernet Alliance • Gigabit Ethernet is an extension of the highly successful 10mbps (10base-t) Ethernet and 100mbps (100base-t) fast Ethernet standards for network connectivity • Gigabit Ethernet incorporates enhancements that enable fast optical fiber connections at the physical layer of the network
Specifications • CSMA/ CD MAC engine • Cabling base standards • 1000BASE-SX • 1000BASE-LX • 1000BASE-CX • 1000BASE-T
Standards 1000 Mbps CSMS/CD MAC IEEE 802.3ab standard IEEE 802.3z standard Two pairs of twinax Two standards of MMF or SMF fiber Two standards of MMF Four pairs of cat 5 UTP or better
Gigabit Ethernet MAC • It uses the official 802.3 frame format • Operates in both half- and full-duplex mode • Slot time has increased to 512 bytes • Burst mode – multiple smaller frames can be transmitted continuously up to a maximum of 8192 bytes of data
Gigabit Ethernet PHYs • The 802.3z Gigabit Ethernet includes three PHYs: 1000BASE-SX and LX to support fiber optic cable and 1000BASE-CX for shielded 150-ohm copper cable • 802.3ab 1000BASE-T physical layer, which enable Gigabit Ethernet over category 5 UTP
1000BASE-SX • Targeted at cost sensitive • Shorter backbone • Horizontal connection • 850nm short-wavelength optical diodes • Multimode fiber (MMF) • 220 to 550 meters distance depending on the type of fiber cable used
1000BASE-LX • Targeted at longer backbone • Vertical connections • It can use either SMF or MMF • For LX, using MMF • 550m, full duplex • For SX, using SMF • 5000m
1000BASE-CX • Designed for short interconnects of hubs, switches, or routers in wiring closet • 150- twinax cabling • Max cable length is 25 meters • Two types of connectors • High-Speed Serial Data Connector (HSSDC) • Nine-pin D-subminiature connector
1000BASE-T • It uses all four pairs of Cat 5 cabling • Simultaneous transmission and reception on all four pairs – Dual Duplex • High symbol rate of 125MHz
Advantages • 10 times faster than fats Ethernet • 100 times faster than Ethernet • Low implementation cost • Compatible with the most popular networking architecture
Advantages • Increased network performance levels • Increased network scalability • Full duplex • Switched • No inherent distance limitations
Advantages • Relatively simple installation and maintenance • Fast optical fiber connections at the physical layer of the network • Provides a tenfold increase in MAC (media access control) layer data rates to support video conferencing, complex imaging and other data-intensive applications
References • Business Data Communication, William Stallings, Fourth Edition • Switched, Fast and Gigabit Ethernet, Robert Breyer & Sean Riley • http://www.aj.com • http://www.10gea.org • http://www.betanet.co.uk/