CHAPTER 4 | Making Network
Connections
Connectivity
Rules

CONNECTIVITY RULES

When adding hubs (repeaters) to your network, pl ease fo ll ow th e c o nnectivit y
rules listed in the manuals for these products. However, note that because
switches break up the path for connected devices into sepa rate collision
domains, you should not include the switch or connected cabling in
your
calculations
for cascade length involving other devices.

1000BASE-T CABLE

R
EQUIREMENTS
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) o r C a tegory 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.

10 GBPS ETHERNET COLLISION

D
OMAIN
Table 6: Maximum 1000BASE-SX Gigabit Ether net Cab le Lengths
Fiber Size Fiber Bandwidth Maximum Cable Length Connector
62.5/125 micron
single-mode fiber
160 MHz/km 2-26 m (7-85 ft.) LC
200 MHz/km 2-33 m (7-108 ft.) LC
50/125 micron
single-mode fiber
400 MHz/km 2-66 m (7-216 ft.) LC
500 MHz/km 2-82 m (7-269 ft.) LC
2000 MHz/km 2-300 m (7-984 ft.) LC

Table 7: Maximum 10GBASE-LR 10 Gigabit Ethernet Cable Length
Fiber Size Fiber Bandwidth Maximum Cable Length Connector
9/125 micron single-
mode fiber
N/A 10 km (6.2 miles) LC

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