Cisco Systems CRS-1 Network Router User Manual


 
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Cisco CRS-1 Carrier Routing System SIP and SPA Hardware Installation Guide
OL-7113-05
Chapter 3 Overview: Cisco CRS-1 Shared Port Adapters
5-Port Gigabit Ethernet SPA Overview
Insert a 5-dB inline optical attenuator between the fiber-optic cable plant and the receiving port on
the 1000BASE-ZX module at each end of the link whenever the fiber-optic cable span is equal to or
greater than 15.5 miles (25 km) but less than 31 miles (50 km).
SFP Module Cabling and Connection Equipment
Table 3-16 provides cabling specifications for the SFP modules that can be installed on the 5-Port
Gigabit Ethernet SPA. Note that all SFP ports have LC-type connectors.
The minimum cable distance for the SFP-GE-S is 6.5 feet (2 m), and the minimum link distance for the
SFP-GE-Z is 6.2 miles (10 km) with an 8-dB attenuator installed at each end of the link. Without
attenuators, the minimum link distance for the SFP-GE-Z is 24.9 miles (40
km).
Note The 1000BASE-ZX SFP modules provide an optical power budget of 21.5 dB. You should measure your
cable plant with an optical loss test set to verify that the optical loss of the cable plant (including
connectors and splices) is less than or equal to 21.5 dB. The optical loss measurement must be performed
with a 1550-nm light source.
Ta b l e 3-16 SFP Module Port Cabling Specifications
SFP Modules
Wavelength
(nm)
Fiber Type
Core Size
(micron)
Modal
Bandwidth
(MHz/km)
Maximum
Cable Distance
SFP-GE-S 850 MMF
1
1. Multimode fiber (MMF) only.
62.5 160 722 ft (220 m)
62.5 200 984 ft (300 m)
50.0 400 1640 ft (500 m)
50.0 500 1804 ft (550 m)
SFP-GE-L 1300 MMF
2
and
SMF
2. A mode-conditioning patch cord is required.
When using the SFP-GE-L with 62.5-micron diameter MMF, you must install a mode-conditioning patch cord between the
SFP module and the MMF cable on both the transmit and the receive ends of the link when link distances are greater than
984
ft (300 m).
We do not recommend using the SFP-GE-L and MMF with no patch cord for very short link distance (tens of meters). The
result could be an elevated bit error rate (BER).
62.5 500 1804 ft (550 m)
50.0 400 1804 ft (550 m)
50.0 500 1804 ft (550 m)
9/10 6.2 miles (10 km)
SFP-GE-Z 1550 SMF 9/10 49.7 miles
(80
km)
SMF
3
3. Dispersion-shifted single-mode fiber-optic cable.
8 62.1 miles
(100
km)