This read-only counter reports the total bytes, rather than packet count, received on a specific interface and address family that were rejected by Reverse Path Forwarding (RPF, anti-spoofing) checking. A network security engineer uses this alongside jnxRpfStatsPackets to understand not just how many but how much traffic volume is being rejected as spoofed, which helps gauge whether an RPF-triggering event is a minor probe or a substantial attack. For example, a high byte count paired with a relatively low packet count of RPF drops would suggest large packets, potentially a reflection/amplification attempt, are being rejected rather than many small probe packets.