Chapter 2
Switch Installation
Installation Guidelines
When deciding where to place the switch, be sure to observe these requirements:
•
•
Table 2-1
SFP Module
100BASE-FX
1000BASE-BX
1000BASE-LX/LH
1000BASE-SX
1000BASE-ZX
CWDM
1. A mode-conditioning patch cord is required. Using an ordinary patch cord with MMF, 1000BASE-LX/LH SFP modules, and
2. 1000BASE-ZX SFP modules can send data up to 62 miles (100 km) by using dispersion-shifted SMF or low-attenuation
OL-6336-06
For copper Ethernet ports, including 10/100 ports, 10/100/1000 ports, and 1000BASE-T SFP
module ports, cable lengths from the switch to connected devices can be up to 328 feet (100 meters).
Table 2-1
lists the cable specifications for 1000BASE-SX, 1000BASE-LX, 1000BASE-ZX, and
CWDM fiber-optic SFP module connections. Each port must match the wave-length specifications
on the other end of the cable, and for reliable communications, the cable must not exceed the
stipulated cable length.
Fiber-Optic SFP Module Port Cabling Specifications
Wavelength
(nanometers)
Min.: 1270
Typical: 1300
Max.: 1380
1490/1310
1300
850
1550
1470, 1490,
1510, 1530,
1550, 1570,
1590, 1610
a short link distance can cause transceiver saturation, resulting in an elevated bit error rate (BER). When using the LX/LH
SFP module with 62.5-micron diameter MMF, you must also install a mode-conditioning patch cord between the SFP module
and the MMF cable on both the sending and receiving ends of the link. The mode-conditioning patch cord is required for link
distances greater than 984 feet (300 m).
When using shorter distances of single-mode fiber cable, you might need to insert
Note
an inline optical attenuator in the link to avoid overloading the receiver.
When the fiber-optic cable span is less than15.43 miles (25 km), at each end of
the link, insert a 5-decibel (dB) or 10-dB inline optical attenuator between the
fiber-optic cable plant and the receiving port on the 1000BASE-ZX SFP module
SMF; the distance depends on the fiber quality, the number of splices, and the connectors.
Core Size
Fiber Type
(micron)
MMF
50/125
62.5/125
SMF
9
1
MMF
62.5
50
SMF
50
9/10
MMF
62.5
62.5
50
50
SMF
9/10
SMF
9/125
Catalyst 3750 Switch Hardware Installation Guide
Preparing for Installation
Modal
Bandwidth
(MHz/km)
Cable Distance
500
6,562 feet (2 km)
—
32,810 feet (10 km)
500
1804 feet (550 m)
400
1804 feet (550 m)
500
1804 feet (550 m)
—
32,810 feet (10 km)
160
722 feet (220 m)
200
902 feet (275 m)
400
1640 feet (500 m)
500
1804 feet (550 m)
—
43.4 to 62 miles (70
2
to 100 km)
—
62 miles (100 km)
2-5