First,with the East & West Add-Drop CWDM OADM coarse wavelength optical add / drop multiplexer, one or more new access points can be added anywhere in the CWDM long-distance optical transport network without affecting other channels in the entire network. In order to improve network transmission Efficiency, WDM technology is often deployed in equipment.
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Why CWDM & DWDM combination network can be achieved
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