This value sets the new DSCP (Differentiated Services Code Point) marking that gets applied to a packet's IP header when a QoS policy determines the traffic has exceeded its configured rate limit. Administrators use it to implement rate-limiting policies that remark out-of-profile traffic to a lower-priority DSCP value rather than outright dropping it, so it's still forwarded but deprioritized. For example, setting this to 8 (a low-priority class) would cause traffic exceeding its committed rate to be downgraded to best-effort-like handling elsewhere in the network.