PRBS can be used to test that the SDH service is healthy and that the protection reversal function is working.
The number of bit False blocks on each VC4 channel is detected by B3 on the receiving side. At the same time, the information is sent back to the sender via Q, and HP-REI and HP-FEBBE report on the sender.
The difference between dispersion compensation fibers and ordinary optical fibers is that the dispersion compensation fibers have a negative dispersion coefficient at ().
Which of the following are device-level protection schemes for SDH products? (Multiple choice).
An unprotected chain consists of four net elements; ME1, NE2, NE3 and NE4.
Create an end-to-end VC4 path NE1-NE4 and add NE5 between NE2 and NE3 for capacity expansion.
The original configuration remains unchanged and no services are configured on the NE5.
In this case, the unprotected chain becomes NE1-NE2-NE5NE3-NE4, how many VC4 paths can be searched?
When the low-level resources of the device are insufficient, which of the following measures can be taken? (Multiple choice).
SES: There are 5% or more of the False blocks or at least one defect (OCI/AIS/LCK/IAE/LTC/TIM/PLM) in one second.
When the ACT indicator of the SDH board is off, it means that the board has a hardware failure and cannot be used.
TESTED 22 Feb 2025
