NO.241 Before the optical power commissioning of an ROADM board, you need to configure virtual optical-layer services. Otherwise, the ROADM board blocks all wavelengths by default.
- A. True
- B. False
NO.242 Which of the following standards must be met for the isolation test in the feature test of the multiplexer/demultiplexer?
- A. > 25dB
- B. > 20dB
- C. < 25dB
- D. < 20dB
NO.243 The LOA board can implement the L2 scheduling function of the Ethernet in OSN 1800.
- A. True
- B. False
NO.244 If no bit error test is performed on a optical channel for 10 minutes, the local end uses the SDH analyzer to connect to the client-side port on the OTU board, the client-side port on the opposite OTU board need to be self-looped by a fiber. In the case of self-loop, a fixed attenuator must be added.
- A. False
- B. True
NO.245 Which of the following Optical NE types are defined in U2000?
- A. WDM_OEQ
- B. WDM_OTM
- C. WDM_OLA
- D. WDM OADM
NO.246 When creating new NE,which of the following Configuration Mode can be selected?
- A. Initialize and Manually Configure NE Data
- B. Download
- C. Upload
- D. Copy NE Data
NO.247 The causes of discrete services are as follows:
- A. A subnet service whose source or sink port is not in the management scope of the U2000 is available.
- B. The logical fiber connection of the NE is inconsistent with the physical fiber connection.
- C. The configuration data on the NE side is not uploaded to the U2000.
- D. The cross-connection configuration on the NE is incorrect.
NO.248 The maximum output optical power of an OBU board is 20 dBm, when it is used in a C-band 80-channel system, what is the standard per-channel output optical power?
- A. -2dBm
- B. +4dBm
- C. +ldBm
- D. +7dBm
NO.249 When many alarms are reported at the same time, the alarm handling priority is as follows: Handle alarms according to the priorities of equipment alarms (such as BUS_ERR, HARD_ERR, and COMM_FAIL), optical-layer LOS, electrical-layer OTUk_LOF, ODUk_SSF, and protection switching.
- A. True
- B. False
NO.250 Which of the following statements about the modulation technologies of the 40Gbit/s and 100Gbit/s coherent systems are correct?
- A. The modulation technology used in a 40G coherent system is ePDM-QPSK.
- B. The modulation technology used in a 100G coherent system is ePDM-QPSK.
- C. The modulation technology used in a 100G coherent system is ePDM-BPSK.
- D. The modulation technology used in a 40G coherent system is ePDM-BPSK.
NO.251 If tunnel APS is configured for the tunnel to which the PW belongs, PW APS cannot be configured for the PW.
- A. False
- B. True
NO.50 Dispersion compensation is not required for 40 Gbit/s and 100 Gbit/s coherent systems because the dispersion tolerance of coherent boards is large. NG WDM products do not support hybrid transmission of non-coherent and coherent networks.
- A. True
- B. False
NO.252 In the scenario where the non-convergence OTU processes OTN standard signals, both A and B are WDM sites.The OTU at station A accesses four channels of R_LOS signals on the client side. After being processed in the middle part and on the WDM side of the OTU at station A, the alarm signals are then sent to station The ODUk_PM_AIS alarm of the corresponding channel is generated in the middle part of station The ODUk_PM_AIS alarm is detected in the client device.
- A. True
- B. False
NO.253 MPLS APS is a network protection mechanism. It implements service switching by using the MPLS OAM detection function.
- A. True
- B. False
NO.254 The overhead ratio is a factor that affects the error correction capability of the FEC technology. Generally, when the same FEC encoding/decoding algorithm is used, the higher the overhead ratio is, the larger the net coding gain is.
- A. False
- B. True
NO.255 For the MSTP equipment, the pass-through mode is used for VC-4 services by default, and the termination mode is used for VC12/VC3 services by default.
- A. True
- B. False