Chapter 3 Installing Ethernet Switching Modules
Attaching the Network Interface Cables
Figure 3-8 Mode Conditioning Patch Cord with LC (SFP Transceiver) Connector
2
RX TX
1 | Gray color identifier | 2 | To gigabit Ethernet interface |
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3 | Blue color identifier | 4 | Multimode fiber |
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5 | Single-mode fiber | 6 | Offset junction |
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7 | Beige color identifier | 8 | To cable plant |
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The mode-conditioning patch cord assembly is composed of duplex optical fibers, including a single-mode-to-multimode offset launch fiber connected to the transmitter, and a second conventional graded-index multimode optical fiber connected to the receiver. The use of a plug-to-plug patch cord maximizes the power budget of multimode 1000BASE-LX/LH links.
Note The mode-conditioning patch cord is required to comply with IEEE standards. The IEEE found that link distances could not be met with certain types of fiber-optic cable cores. The solution is to launch light from the laser at a precise offset from the center, which is accomplished by using the mode-conditioning patch cord. At the output end of the patch cord, the GBIC-LX/LH is compliant with the IEEE 802.3z standard for 1000BASE-LX.
Catalyst 6500 Series Ethernet Modules Installation Guide
