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Chapter 1
Describing the optical routing system
Nortel Networks* optical routing system uses coarse wavelength division multiplexing (CWDM) in a grid of eight optical wavelengths. CWDM Gigabit Interface Converters (GBICs) in the switch transmit optical signals from Gigabit Ethernet ports to multiplexers in a passive optical shelf. Multiplexers combine multiple wavelengths traveling on different fibers onto a single fiber (Figure 1). At the receiver end of the link, demultiplexers separate the wavelengths again and route them onto different fibers which terminate on separate CWDM GBICs at the destination. The system supports both ring and
Figure 1 Wavelength division multiplexing
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| 10539EA |
This chapter includes the following topics:
•“Parts of the optical routing system” next
•“Gigabit interface converter description” on page 18
•“Optical add drop multiplexer description” on page 19
•“Optical multiplexer/demultiplexer description” on page 21