What is network performance metrics?
Why Interviewers Ask This
This tests whether you can apply Networking knowledge to real-world scenarios. Interviewers are looking for clarity of thought and evidence that you've encountered this in production code.
Answer
Key network performance metrics for monitoring and troubleshooting: Latency — round-trip time (RTT) in milliseconds; measured with ping. Jitter — variation in latency; critical for real-time applications (VoIP, video); measured with iperf or MOS scores. Packet Loss — percentage of packets that do not reach the destination; even 1% causes significant TCP throughput degradation. Throughput — actual data transfer rate achieved; measured with iperf3. Bandwidth Utilization — percentage of link capacity in use; consistently above 70-80% indicates need for upgrade. Error Rate — CRC errors, input/output errors on interfaces (hardware issues, bad cables). CPU/Memory utilization on network devices (high CPU can indicate routing issues or attacks). Interface errors — drops (queue overflow), input errors (corrupt frames). Tools: iperf3 (throughput testing), ping/traceroute, Wireshark, SNMP-based monitoring (PRTG, Zabbix), NetFlow analysis. SLA definitions typically specify maximum acceptable latency, jitter, and packet loss for each traffic class.
Pro Tip
This topic has Networking-specific nuances that differ from general programming. Highlighting those nuances in your answer shows expertise rather than generic knowledge.