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H3C Technologies H3C S6300 Series Switches User Manual

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The following parameters that reflect VoIP network performance can be calculated by using the metrics

gathered by the voice operation:

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 of 1 to 5. A higher value represents a higher service quality.

The evaluation of voice quality depends on users' tolerance for voice quality, which you should consider.

For users with higher tolerance for voice quality, use the advantage-factor command to configure the

advantage factor. When the system calculates the ICPIF value, it subtracts the advantage factor to modify
ICPIF and MOS values, so both objective and subjective factors are considered.
The voice operation requires both the NQA server and the NQA client. Before you perform a voice

operation, configure a UDP listening service on the NQA server. For more information about UDP

listening service configuration, see "

Configuring the NQA server

."

The voice operation cannot repeat.
To configure the voice operation:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Create an NQA operation
and enter NQA operation

view.

nqa entry admin-name
operation-tag

By default, no NQA operation is
created.

3.

Specify the voice type and

enter its view.

type voice

N/A

4.

Specify the destination IP
address of voice packets.

destination ip ip-address

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.

5.

Specify the destination port of
voice packets.

destination port port-number

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.

6.

Specify the codec type.

codec-type { g711a | g711u |
g729a }

By default, the codec type is G.711
A-law.

7.

Specify the advantage factor
for calculating MOS and

ICPIF values.

advantage-factor factor

By default, the advantage factor is 0.

8.

(Optional.) Specify the source
IP address of voice packets.

source ip ip-address

By default, no source IP address is
specified.
The source IP address must be the IP
address of a local interface, and the

interface must be up. Otherwise, no

voice packets can be sent out.

9.

(Optional.) Specify the source
port number of voice packets. source port port-number

By default, no source port number is
specified.