This read-only counter tracks the total number of bytes received by the system since it last booted, covering both cut-through traffic and host traffic. An admin uses it alongside wgSystemTotalSendBytes to establish a baseline inbound/outbound traffic ratio and spot abnormal shifts that might indicate a DDoS attempt or bandwidth-hogging application. For example, comparing wgSystemTotalRecvBytes deltas across successive 5-minute polls lets the admin build a throughput graph for the appliance's inbound traffic.