Huawei Huawei Certifications H31-321 Questions & Answers

• Question 71:

  Which tools or meters must you prepare before commissioning SDH equipment?

  A. Spectrum analyzer

  B. SDH analyzer

  C. Optical attenuator

  D. BER tester

  E. Oscilloscope

  F. Multimeter

  Correct Answer: BCDF

• Question 72:

  Alarm signals on the PDH ports working at different rates differ. Which of the following are true?

  A. The T_ALOS alarm is reported when external signals are lost on an El electrical interface board.

  B. The P_LOS alarm is reported when external signals are lost on an E3 or E4 electrical interface board.

  C. The DOWN_El_AIS is reported when an El electrical interface board detects all "l"s in the downstream signal stream.

  D. The UP_E1_AIS is reported when an El electrical interface board detects all "l"s in the upstream signal stream.

  E. The PAIS is reported when an E3 electrical interface board detects all "l"s in signal streams.

  Correct Answer: ACDE

• Question 73:

  Which of the following about the SSM protocol are true?

  A. After the SSM protocol is disabled, the clock network can be unidirectional but cannot adopt a ring

  B. topology.

  C. After the standard SSM protocol is enabled, the clock network can be bidirectional but cannot adopt a ring topology.

  D. After the extended SSM protocol is enabled, the clock network can be bidirectional and adopt a ring topology, which can be intersecting or tangent with other networks.

  E. The SSM protocol has little to do with clock networks.

  Correct Answer: AB

• Question 74:

  Which of the following may cause abnormal ECC communication?

  A. The optical port reports the B3_SD alarm. What may cause the HPJ.OM alarm?

  B. The two interconnected optical boards have different rates.

  C. The local NE uses Dl to D3, but the peer NE uses Di to D3 and D4 to D12.

  D. The local NE uses Dl to D3, but the peer NE uses D4 to D12.

  E. The DCC bytes of the optical board have been deleted.

  Correct Answer: BDE

• Question 75:

  Which file needs to be modified on the U2000 to change the VC-12 timeslot numbering policy?

  A. trans_ems.cfg

  B. locale, properties

  C. ems.cfg

  D. imap.cfg

  Correct Answer: A

• Question 76:

  Which of the following statements are True about J1 and C2 bytes on NG-SDH equipment?

  A. For VC-4 services, a line board detects both J1 and C2 bytes.

  B. For VC-4 services, a line board does not detect J1 or C2 bytes.

  C. For VC-12 services, a line board detects both J1 and C2 bytes,

  D. For VC-12 services, a line board does not detect J1 or C2 byte.

  Correct Answer: BC

• Question 77:

  To objectively evaluate the performance of a network packet switching device, define test methods, and test report formats, you need to perform RFC 2544 performance tests. What does an RFC 2544 test cover?

  A. Throughput

  B. Packet loss rate

  C. Latency

  D. Back-to-back

  E. Maximum frame rate (line rate)

  Correct Answer: ABCD

• Question 78:

  You can change the VC-12 numbering policy by configuring related parameters on the U2000.

  A. TRUE

  B. FALSE

  Correct Answer: B

• Question 79:

  Which of the following are true about laser safety operations?

  A. When installing or maintaining an optical interface board or optical fibers, do not look into the optical interface board or fiber connectors.

  B. You need to disconnect the fiber jumper from the optical interface board of the peer NE when using an optical time domain reflectometer (OTDR).

  C. Use protective caps to cover unused optical ports and optical connectors of fiber jumpers.

  D. You can replace optical interface boards or optical modules during equipment-side maintenance.

  Correct Answer: ABC

• Question 80:

  What are the common causes for an SNCP switching failure?

  A. Hardware faults

  B. Incorrect fiber connections between boards

  C. Incorrect setting of protection group parameters

  D. Incorrect setting of hold-off time

  Correct Answer: ABC