A.The pulse width of emitted optical pulses varies according to monitoring modes, and affects the detection distance and measurement precision. A greater pulse width provides a larger dynamic range, longer detection distance and better measurement precision.

B.When the pulse width increases, the light emitting time increases and consequently a larger energy is obtained. This means that a larger dynamic range can be acquired but also larger dead zones will result.

C.Measurement is performed multiple times within the detection time. The average value is obtained based on the measurement results to improve the measurement precision. The actual duration from the time when a detection event starts to the time when the detection results are returned will be longer than the Detection time.

D.The total fiber loss will affect the detection distance and the dynamic range is fixed for the same detection mode. Therefore, a larger total fiber loss indicates a smaller detection distance.

A.Chain type

B.Ring

C.Mesh

D.Point to point

A.L is in standard Ethernet frame length with a minimum value of 64Bytes

B."8" outside the brackets is 1 Byte containing 8 Bits

C.M is the frame gap, and the minimum IFG (minimum frame gap) is 8 bytes.

D.Rate indicates the line rate of the physical layer. If the device port is FE, then Rate=100Mbit/s.

A.The network administrator cannot obtain the current notifications of the device, the alarm occurrence time, and the historical alarm of the device.

B.In the case of complex networking, service, and fault information, many alarms and performance events may occur along with the occurrence of faults. Due to too many reports and performance events, maintenance personnel are unable to analyze.

C.When some faults occur, there may be no obvious alarms or performance events reported, and sometimes no alarms or performance events are found.

D.Field maintenance personnel cannot understand the current operating condition of the equipment.

A.Waiting for the recovery time to be set too long

B.Electrical cross configuration error

C.SNCP type setting error

D.Set the lock or forced switch command