Connectivity Rules 4
The 1000BASE-SX, 1000BASE-LX and 1000BASE-ZX fiber optic ports operate at 1 Gbps full duplex. The maximum length for fiber optic cable operating at Gigabit speed will depend on the fiber type as listed under “1000 Mbps Gigabit Ethernet Collision Domain” on page 4-5.
Connectivity Rules
When adding hubs (repeaters) to your network, please follow the connectivity rules listed in the manuals for these products. However, note that because switches break up the path for connected devices into separate collision domains, you should not include the switch or connected cabling in your calculations for cascade length involving other devices.
1000BASE-T Cable Requirements
All Category 5 UTP cables that are used for 100BASE-TX connections should also work for 1000BASE-T, providing that all four wire pairs are connected. However, it is recommended that for all critical connections, or any new cable installations, Category 5e (enhanced Category 5) or Category 6 cable should be used. The Category 5e specification includes test parameters that are only recommendations for Category 5. Therefore, the first step in preparing existing Category 5 cabling for running 1000BASE-T is a simple test of the cable installation to be sure that it complies with the IEEE 802.3-2005 standards.
1000 Mbps Gigabit Ethernet Collision Domain
Table 4-1 Maximum 1000BASE-T Gigabit Ethernet Cable Length
Cable Type | | Maximum Cable Length | Connector |
Category 5, 5e, 6 100-ohm UTP or STP | 100 m (328 ft) | RJ-45 |
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Table 4-2 Maximum 1000BASE-SX Fiber Optic Cable Length |
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Fiber Diameter | Fiber Bandwidth | Cable Length Range | | Connector |
| | | | | |
62.5/125 micron multimode | 160 MHz/km | | 2-220 m (7-722 ft) | | LC |
fiber (MMF) | | | | | |
200 MHz/km | | 2-275 m (7-902 ft) | | LC |
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50/125 micron multimode fiber | 400 MHz/km | | 2-500 m (7-1641 ft) | | LC |
(MMF) | | | | | |
500 MHz/km | | 2-550 m (7-1805 ft) | | LC |
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