Triple-Play Service Deployment

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R-Value
Testing the Premises Network to Ensure Service Quality
R-Value vs. Delay
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Delay
Figure 5.3 Voice quality degradation based on delay (in microseconds)
Chapter 5: Troubleshooting the Premises Wiring
G.107
Default
G.711
G.729
User Satisfaction MOS
Very Satisfied 4.4
Satisfied 4.3
Some Users Dissatisfied
4.0
Many Users Dissatisfied
Nearly All Users Dissatisfied
Not Recommended
3.6
3.1
2.6
1.0
Residential network performance metrics, such as loss, latency, and
jitter can have a significant impact on service quality. It is
particularly important to consider the interwoven ramifications of
correcting the individual effects. While jitter can be overcome by
increasing the jitter buffers of the receiving equipment, this action
will increase latency as well as the cost of the equipment.
Additionally, if the jitter buffer is too small, then packet loss can be
caused by noise in the system or service capacity issues. A realtime
protocol such as VoIP or IPTV does not retransmit lost packets.
The result is an impairment that directly affects the perceived
quality of service and the customer’s QoE.
R
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