R3166-R3206-HP High-End Firewalls High Availability Configuration Guide-6PW101

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Upon receiving the packet, the source calculates results, such as the delay jitter and one-way delay
based on the packet time stamps. The statistics reflect network performance.
Voice test result also includes the following parameters that reflect VoIP network performance:
• Calculated Planning Impairment Factor (ICPIF)—Measures impairment to voice quality in a VoIP
network. 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 the
range 1 to 5. A higher value represents a higher quality of a VoIP network.
The evaluation of voice quality depends on users’ tolerance to voice quality, which should be taken into
consideration. For users with higher tolerance to voice quality, use the advantage-factor command to
configure the advantage factor. When the system calculates the ICPIF value, this advantage factor is
subtracted to modify ICPIF and MOS values, so objective and subjective factors are both considered
when you evaluate the voice quality.
Configuration prerequisites
Voice 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 service
configuration, see ”Configuring the NQA server.”
Configuring voice tests
Follow these steps to configure voice tests:
To do… Use the command…
Remarks
Enter system view System-view —
Enter NQA test group view
nqa entry admin-name
operation-tag
—
Configure the test type as voice
and enter test type view
type voice Required
Configure the destination address
of voice probe packets
destination ip ip-address
Required
By default, no destination IP address is
configured.
The destination IP address must be the
same as that of the listening service on
the NQA server.
Configure the destination port of
voice probe packets
destination port port-number
Required
By default, no destination port number is
configured.
The destination port must be the same as
that of the listening service on the NQA
server.
Configure the codec type
codec-type { g711a | g711u
| g729a }
Optional
By default, the codec type is G.711
A-law.
Configure the advantage factor for
calculating MOS and ICPIF values
advantage-factor factor
Optional
By default, the advantage factor is 0.