Similar to a scheduler context within a scheduler-policy, the policer-control-policy contains objects called arbiters that control the amount of bandwidth that may be distributed to a set of child policers. Each policer control policy always contains a root arbiter that represents the parent policer. The max-rate defined for the arbiter specifies the decrement rate for the parent policer that governs the overall aggregate rate of every child policer associated with the policy instance. The root arbiter also contains the parent policers MBS configuration parameters that the system uses to individually configure the priority thresholds for each policer instance.
Child policers may parent directly to the root arbiter or to one of the tier 1 or tier 2 explicitly created arbiters.
Each arbiter provides bandwidth to its children using eight strict levels. Children parented at level 8 are first to receive bandwidth. The arbiter continues to distribute bandwidth until either all of its children's bandwidth requirements are met or until the bandwidth it is allowed to distribute is exhausted. The root arbiter is special in that its strict priority levels directly represent the priority thresholds within the parent policer.