3com Hub 1000 SX Manual De Usuario
3
M
AKING
C
ONNECTIONS
This chapter contains guidelines for making typical Hub 1000 SX network
connections and for troubleshooting problems with the hub.
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.
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.
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.
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.
Hub 1000 SX downlink degrades the performance on the link to
the switch.
Table 3-1 Gigabit Ethernet Maximum Cable Lengths
Signal Type
Laser
Wavelength
Wavelength
Connector
Type
Type
Cable Type
50/125
µ
Multimode
Fiber
Fiber
62.5/125
µ
Multimode
Fiber
Fiber
Single-Mode
Fiber
Fiber
Shielded
Balanced Pair
(Coaxial Jumper)
Balanced Pair
(Coaxial Jumper)
1000BASE-SX
Short
(850 nm)
(850 nm)
SC
550 meters
260 meters
N/A
N/A
1000BASE-LX
*
Long
(1300 nm)
(1300 nm)
SC
550 meters
440 meters
3 kilometers
N/A
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.