LevelOne GSW-2476 user manual Connectivity Rules, 1000BASE-T Cable Requirements

MAKING NETWORK CONNECTIONS

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		Connector
		Length
Category 5, 5e, 6 100-ohm UTP or STP		100 m (328 ft)		RJ-45
Table 4-2 Maximum 1000BASE-SX Fiber Optic Cable Length
Fiber Diameter	Fiber		Cable Length	Connector
	Bandwidth		Range
62.5/125 micron	160 MHz/km		2-220 m (7-722 ft)	LC
multimode fiber (MMF)
	200 MHz/km		2-275 m (7-902 ft)	LC
50/125 micron	400 MHz/km		2-500 m (7-1641 ft)	LC
multimode fiber (MMF)
	500 MHz/km		2-550 m (7-1805 ft)	LC

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