Cisco Cisco MGX-FRSM-HS2 B Serial Frame Service Module Libro blanco

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issues with VoIP traffic during peak hours. Applying an appropriate QoS scheme eliminated this problem. See Figure

Figure 9. Traffic Distribution After QoS Is Implemented

Use Case: Voice Quality Thresholds for Proactive Troubleshooting

To manage voice quality proactively the system should automatically alert you to potential problems. This is

achieved on the NAM through the use of thresholds and alerts. As shown in Figure 9, a number of metrics can be

configured for alerts. MOS thresholds can be configured with different values for different codecs because the quality

tolerances could be different depending on the codec. In addition, jitter, seconds of concealment, and packet loss

can be configured with thresholds based on the requirements of the network. Preset default values are provided and

can be modified as needed.

Alerts are sent as syslog messages; therefore, the NAM should be configured to export alerts to a specific syslog

receiver. In a typical enterprise, a syslog receiver collects syslog messages from various devices and feeds them

into a network or performance management product that processes the message. Figure 10 shows the various

thresholds that can be configured. This capability would be useful when different MOS tolerances are required for

each codec.