Configuring Voice Tests - HP 5500 EI Series Configuration Manual

Step
7. Configure the string to be
filled in the data field of
each UDP packet.
8. Specify the source port of
UDP packets.
9. Configure the source IP
address of UDP packets.
10. Configure optional
parameters.

Configuring voice tests

IMPORTANT:
Do not perform voice tests on known ports, ports from 1 to 1023. Otherwise, the NQA test might fail or the
corresponding services of these ports might be unavailable.
Voice tests of an NQA test group are used to test voice over IP (VoIP) network status, and collect VoIP
network parameters so that users can adjust the network.
A voice test performs the following procedure:
1. The source (NQA client) sends voice packets of G.711 A-law, G.711 μ-law or G.729 A-law
codec type at regular intervals to the destination (NQA server).
2. The destination affixes a time stamp to each voice packet that it receives and then sends it back to
the source.
3. 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 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 into
consideration. 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, this advantage factor is
subtracted to modify ICPIF and MOS values, so objective and subjective factors are both considered
when you evaluate voice quality.
Command
data-fill string
source port port-number
source ip ip-address
See "Configuring
optional parameters for
an NQA test group"
127
Remarks
Optional.
By default, the string is the hexadecimal number
00010203040506070809.
Optional.
By default, no source port number is specified.
Optional.
By default, no source IP address is specified.
The source IP address must be that of an interface
on the device and the interface must be up.
Otherwise, no probe packets can be sent out.
Optional.