Jitter Trends

Monitoring > Tunnel Health > Jitter > Trends

Charts on the Jitter Trends tab show tunnel jitter in milliseconds over time. By default, the charts show average jitter recorded within graphed intervals.

Jitter is the variation in the time between packets arriving, caused by network congestion, timing drift, or route changes. Achieving low jitter values is critical to maintaining the quality of real-time applications, especially voice, video, and other latency-sensitive services.

To display the highest (peak) jitter that occurred during each interval, click Peaks. This helps to quickly spot periods where network jitter spiked, which average jitter statistics might not reveal. If you look only at averages, short bursts of high jitter might go unnoticed, even though they can disrupt voice or video streams. In real-time mode, peaks are always shown.

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NOTE: Underlay tunnels are a shared resource among overlays. Therefore, underlay charts display aggregated data.

Jitter Trend Interpretation Guidelines

Follow the guidelines below to interpret jitter trends in your network tunnel traffic and take appropriate actions to maintain optimal network and application performance.

  • Set Baselines: Establish a baseline for acceptable jitter levels based on the requirements of your applications. For example, VoIP typically requires jitter to be below 30 milliseconds for good call quality.

  • Monitor Trends: Use monitoring tools to continuously track jitter values over time. Look for patterns or spikes that deviate from the baseline.

  • Identify Patterns: Consistent High Jitter: Indicates chronic network issues such as persistent congestion, poor routing, or inadequate bandwidth.

  • Intermittent Jitter Spikes: May suggest temporary issues like traffic bursts, transient congestion, or route flapping.

  • Gradual Increase in Jitter: Could indicate a growing network load or emerging congestion problems that need to be addressed.

  • Correlate with Other Metrics: Check other performance metrics such as latency, packet loss, and throughput to gain a comprehensive understanding of network health. For example, high jitter combined with high packet loss may indicate severe congestion or faulty network equipment.

  • Analyze Traffic Patterns: Determine if jitter issues correlate with specific times of day, specific applications, or particular traffic patterns. This can help identify whether the problem is related to peak usage times or specific application demands.

  • Investigate Network Links: Examine the performance of individual network links and paths. High jitter on a particular link may indicate a need for troubleshooting or reconfiguration. Consider performing a path trace to identify where jitter is introduced along the route.

  • Quality of Service (QoS) Policies: Ensure that QoS policies are correctly configured and prioritize real-time traffic. Misconfigured QoS can lead to increased jitter and degraded application performance. Review and adjust QoS settings as necessary to ensure proper prioritization and handling of sensitive traffic.

  • Capacity Planning: Assess whether your current network capacity meets the demands of your applications. If necessary, plan for additional bandwidth or infrastructure upgrades to alleviate congestion and reduce jitter.

  • Implement Redundancy and Failover: Ensure that your configuration includes redundancy and failover mechanisms to maintain performance during link failures or congestion. Utilize multiple paths to distribute traffic and minimize the impact of jitter on critical applications.

  • Use Advanced Features: Leverage dynamic path selection and application-aware routing to optimize traffic flows and reduce jitter.