129• Calculated Planning Impairment Factor (ICPIF)—Measures impairment to voice quality in a VoIPnetwork. It is decided by packet loss and delay. A higher value represents a lower service quality.• Mean Opinion Scores (MOS)—A MOS value can be evaluated by using the ICPIF value, in therange of 1 to 5. A higher value represents a higher quality of a VoIP network.The evaluation of voice quality depends on users’ tolerance for voice quality, which should be taken intoconsideration. For users with higher tolerance for voice quality, use the advantage-factor command toconfigure the advantage factor. When the system calculates the ICPIF value, this advantage factor issubtracted to modify ICPIF and MOS values, so objective and subjective factors are both consideredwhen you evaluate voice quality.Configuration prerequisitesVoice tests require cooperation between the NQA server and the NQA client. Before you start voice tests,configure a UDP listening service on the NQA server. For more information about UDP listening serviceconfiguration, see “Configuring the NQA server.”Configuring voice testsFollow these steps to configure voice tests:To do… Use the command… RemarksEnter system view system-view —Enter NQA test groupviewnqa entry admin-nameoperation-tag —Configure the test type asvoice, and enter test typeviewtype voice RequiredConfigure the destinationaddress of voice probepacketsdestination ip ip-addressRequiredBy default, no destination IP address is configuredfor a test operation.The destination IP address must be the same as thatof the listening service on the NQA server.Configure the destinationport of voice probepacketsdestination portport-numberRequiredBy default, no destination port number isconfigured.The destination port must be the same as that of thelistening service on the NQA server.Configure the codec type codec-type { g711a |g711u | g729a }OptionalBy default, the codec type is G.711 A-law.Configure the advantagefactor for calculatingMOS and ICPIF valuesadvantage-factor factor OptionalBy default, the advantage factor is 0.Specify the source IPaddress of probe packets source ip ip-addressOptionalBy default, no source IP address is specified.The source IP address must be the IP address of alocal interface. The local interface must be up;otherwise, no probe packets can be sent out.Specify the source portnumber of probe packets source port port-number OptionalBy default, no source port number is specified.
