Although ANL adaptive policers apply to all traffic going through the ANL to maintain a positive customer experience and ensure priority traffic is not starved during congestion, they do not differentiate between identical traffic classes belonging to different subscribers.
The per-subscriber policers are enabled automatically when the congestion-override command is enabled and the subscriber is in a congestion state. Typically, the policing rate is set so that it mostly affects heavy users. The congestion override policers can be used for all DEM use cases, such as NLB-DEM and ANL-based DEM. The operator can configure a second-stage congestion override policer. Second stage policers are applied when congestion persists even after applying the override congestion policers. Typically, the operators set a stricter bandwidth control in second stage policers to relieve congestion conditions.
Very similar to Time-of-Day (ToD) policers, per-subscriber congestion policers can be applied to all the traffic of a subscriber, specific applications, or application groups as configured in the matching section of AQPs.