This read-only Counter32 measures the total bytes received in the ingress direction on this port that had the Discard Eligible bit set to 1. It lets an admin see how much of the traffic entering this port is already tagged as discard-eligible before it's even switched, which is useful for tracing whether upstream devices are properly marking excess or best-effort traffic. If this value grows disproportionately relative to total ingress bytes, it may indicate the connected CPE is oversubscribing its committed rate.