单项选择题

You are installing a Cisco ONS 15454 in a service provider site. A DS3 cable is to be connected to a digital cross-connect system. What is the maximum distance allowed between the two?（）

A.225 ft
B.450 ft
C.655 ft
D.900 ft

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热门试题

单项选择题

In the OSNR model for EDFA amplifiers, SNR OUT = 1 (1 SNR IN + FhvB P IN ), what does SNR IN represent?（）

A. the signal to noise of the current optical amplifier
B. the signal to noise of the previous amplifier or source
C. the signal to noise introduced by the optical multiplexer
D. the accumulated noise to signal ratio of the optical channel

单项选择题

Click the Exhibit button. Which type of multiplexer is shown in the exhibit?（）

A. Thin Film filter
B. Fiber Bragg Grating
C. Arrayed Wave Guide
D. Erbium fiber amplifier