This Gauge32 counts how many times the Ethernet receive FIFO overflowed on a receive queue during the current 15-minute period. A growing overflow count means incoming frames are arriving faster than the STU can buffer them, risking silent packet loss even before any CRC or framing errors show up. For example, an unusually bursty subscriber device could push stuCurrEtherRxOver upward, explaining intermittent packet loss that isn't reflected in the CRC error counters.