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 "
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.