User Network Interface (UNI) Requirements and Framework - MEF

UNI Requirements and Framework
100BASE-FX utilizes two strands of the multimode (62.5/125mm) fiber cabling. The maximum
segment length for fiber-optics connections varies. For multimode fiber, it can be 412 meters
while repeater diameters can be up to 320 meters.
The ratio of packet duration to network propagation delay for 100BASE-T is the same as for
10BASE-T. This is since the bit rate is faster, bit times are shorter, packet transmission times are
reduced, and cable delay budgets are smaller, all in proportion to the change in bandwidth.
B.3 1000Base-X/Gigabit Ethernet
1000BASE-X refers to the 1000Mbps MAC and the LX/SX/CX transceiver technology. The
IEEE 802.3z specification couples an extended version of the ISO/IEC 8802-3 (CSMA/CD
MAC) to a family of1000 Mb/s PHY connected through a Gigabit Media Independent Interface
(MII) layer to physical layer entities such as:
• 1000BASE-SX and 1000BASE-LX to support fiber-optics cable
• 1000BASE-T PHY for four pairs of Category 5 balanced copper cabling.
1000BASE-SX is targeted at cost-sensitive, shorter backbone, or horizontal connections. It uses
the same physical layer as LX and uses affordable 850nm short-wavelength optical diodes. It
uses only multimode fiber. Distance supported is 200m to 550m, depending on the type of fiber
cable used.
1000BASE-LX is targeted at longer backbone and vertical connections. It uses single mode or
multimode fiber. It requires 1300nm lasers. Distance supported is 5000m for single mode fiber
while it is 550m for multimode fiber.
1000BASE-T provides a cable length of 100m.
Gigabit Ethernet extends the ISO/IEC 8802-3 MAC beyond 100 Mb/s to 1000 Mb/s. The bit rate
is faster, and the bit times are shorter, both in proportion to the change in bandwidth. In full
duplex mode, the minimum packet transmission time has been reduced by a factor of ten.
Achievable topologies for 1000 Mb/s full duplex operation are comparable to those found in
100BASE-T full duplex mode.
B.4 10GBase-xx/10 Gigabit Ethernet
The newly ratified IEEE 802.3ae standard specifies 10 Gigabit Ethernet that uses the IEEE 802.3
MAC sub layer connected through a 10 Gigabit Media Independent Interface (XGMII) to
Physical layer entities such as 10GBASE-SR, 10GBASE-LX4, 10GBASE-LR, 10GBASE-ER,
10GBASE-SW, 10GBASE-LW, and 10GBASE-EW. Achievable topologies for 10Gbps
operation are comparable to those found in 1000BASE-X full duplex mode and equivalent to
those found in WAN applications.
MEF 11
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