Forward Error Correction Monitoring

  • Published on Sep 29, 2026
  • 3 minute(s) read
  • P
  • S
 Prev Next

What is FEC Monitoring?

Forward Error Correction (FEC) Monitoring provides visibility into how FEC protects traffic between two Graphiant Edges. FEC adds repair packets to protected traffic, allowing the receiving Edge to reconstruct packets lost in transit without requiring application-level retransmission.

Navigate to FEC Monitoring:

To access the FEC Monitoring page:

  1. From the Graphiant Portal, go to Monitor.

  2. Select the required site and Edge.

  3. Select the Network tab.

  4. From the menu on the left, select Forward Error Correction.

The selected Edge is automatically displayed as the source Edge.

Select a peer Edge from the Compare to drop-down menu to display FEC statistics between the two Edges. If a peer Edge is not selected, the page does not display FEC analytics.

Note:

The Forward Error Correction option is visible only when FEC is enabled. FEC is supported only for traffic assigned to the Gold class.

To verify whether FEC is enabled for the organization, go to Organization Settings and review the Network Reliability section.

FEC documentation:  https://docs.graphiant.com/docs/adaptive-fec-at-the-graphiant-edge

You can use FEC Monitoring for:

  • Confirming that traffic is protected by FEC

  • Viewing the FEC repair level

  • Monitoring repair packets sent and received

  • Identifying packets recovered by FEC

  • Identifying packet loss that FEC could not repair

  • Comparing FEC activity in both traffic directions

Traffic Directions

After selecting a peer Edge, the dashboard displays FEC information in both directions:

  • Transmit: Traffic sent from the source Edge to the selected peer Edge.

  • Receive: Traffic received by the source Edge from the selected peer Edge.

For example, if edge-1 is the source Edge and edge-2 is the peer Edge:

  • Transmit: edge-1 → edge-2

  • Receive: edge-2 → edge-1

FEC operates independently in each direction. Therefore, the repair levels and packet counters can differ between the Transmit and Receive directions.

FEC Summary

The summary section provides the following information:

  • Current Repair Level: The overall repair level between the selected Edges. It is calculated by averaging the Transmit and Receive Repair Levels for the selected time window.

  • Unrepairable Rate (5M): A percentage calculated by comparing the number of unprotected packets with the number of protected packets during the five-minute calculation period.

FEC Repair Level Graph

The FEC Repair Level graph shows how the repair level changed during the user-selected time window.

Use the Transmit and Receive controls to view the repair-level graph for each traffic direction.

  • The Transmit graph shows the repair level for traffic sent from the source Edge to the peer Edge.

  • The Receive graph shows the repair level for traffic sent from the peer Edge to the source Edge.

The Edge calculates and reports a repair-level data point every 60 seconds. These data points are displayed as a time series in the graph.

The repair level represents the amount of repair traffic added relative to the original source traffic. Adaptive FEC automatically increases or decreases this level based on the packet-loss conditions detected between the Edges.

Transmit Statistics

The Transmit section displays statistics for traffic sent from the source Edge to the selected peer Edge.

  • Packets Protected: Latest cumulative number of packets protected by FEC.

  • Packets Unprotected: Latest cumulative number of packets transmitted without FEC protection.

  • Repair Packets Sent: Latest cumulative number of FEC repair packets generated and transmitted.

  • Repair Level: Average Transmit repair level calculated from the 60-second samples collected during the selected time window.

Receive Statistics

The Receive section displays statistics for traffic received from the selected peer Edge by the source Edge.

  • Repair Packets: Latest cumulative number of FEC repair packets received.

  • Erasures Recovered: Latest cumulative number of lost source packets successfully reconstructed using FEC repair packets.

  • Erasures Unrepairable: Latest cumulative number of detected packet losses that FEC could not reconstruct.

  • Repair Level: Average Receive repair level calculated from the 60-second samples collected during the selected time window.

Understanding the Time Picker

The time picker controls the time range used to display FEC information. Repair-level information and packet counters are handled differently.

  • The FEC Repair Level graph displays the repair-level data points reported during the selected time window.

  • The Transmit Repair Level is the average of the Transmit repair-level samples collected during the selected time window.

  • The Receive Repair Level is the average of the Receive repair-level samples collected during the selected time window.

  • The Current Repair Level is the average of the calculated Transmit and Receive Repair Levels.

  • Packet counters display the latest cumulative value available at the end of the selected time window.

  • Packet counters do not represent only the packets generated within the selected time window.

Note:

Time ranges such as Past 5 minutes, Past 15 minutes, and Past 2 days may display the same packet-counter values when their end time is the same. This is expected because the packet fields show the latest cumulative value available at the end of the selected period.

Repair Level values can change when a different time range is selected because they are calculated by averaging the repair-level samples available within that time range.

Reset the Peer Comparison

Select Reset Compare to remove the selected peer Edge and return the page to its initial state. You can then select another peer Edge for comparison.

Related articles