This read-only counter tracks the total number of bytes sent by the system since it last booted, covering both cut-through traffic and host traffic. An admin compares this counter's growth rate over time to gauge outbound throughput and identify unusual spikes in egress traffic from the appliance. For example, an unexpectedly steep rise in wgSystemTotalSendBytes over a short polling interval might prompt the admin to investigate a possible data exfiltration or misconfigured bulk transfer.