Packet loss occurs when data packets sent across a network fail to reach their destination. It can result from congestion, faulty links or equipment, configuration problems, or interference. Depending on the protocol and application, lost data may be retransmitted, arrive late, or leave communication incomplete.
In cyber security, packet loss can affect both system performance and the reliability of monitoring or communications. During distributed AI workloads, for example, lost packets can delay exchanges between GPUs and leave processors waiting for data. Attackers may also cause or exploit network disruption, while defenders monitor loss alongside latency and congestion to identify unhealthy paths or possible denial-of-service activity. Packet loss alone does not prove an attack; teams need to correlate network measurements with workload and security telemetry.