3Com Hub 1000 SX manual Making Connections, 1 Gigabit Ethernet Maximum Cable Lengths

3

MAKING CONNECTIONS

This chapter contains guidelines for making typical Hub 1000 SX network connections and for troubleshooting problems with the hub.

When making hub connections, follow the rules for maximum cable lengths, which are summarized in Table 3-1. If you connect 10/100 Mbps devices to the network, rules for Ethernet and Fast Ethernet connections also apply.

Table 3-1Gigabit Ethernet Maximum Cable Lengths

					Cable Type
			50/125 ∝	62.5/125 ∝		Shielded
	Laser	Connector	Multimode	Multimode	Single-Mode	Balanced Pair
Signal Type	Wavelength	Type	Fiber	Fiber	Fiber	(Coaxial Jumper)
1000BASE-SX	Short	SC	550 meters	260 meters	N/A	N/A
	(850 nm)
1000BASE-LX*	Long	SC	550 meters	440 meters	3 kilometers	N/A
	(1300 nm)
1000BASE-CX	N/A	HSSDC	N/A	N/A	N/A	25 meters

* The 1000BASE-LX GBIC module requires an external patch cord for connection to MMF cable.

CAUTION: Connecting the downlink of one Hub 1000 SX to the uplink of a second Hub 1000 SX degrades the performance of the second hub.

CAUTION: Connecting a Gigabit Ethernet switch downlink to a Hub 1000 SX downlink degrades the performance on the link to the switch.