DEM-GW employs adaptive bandwidth policer variants of AA single leaky bucket bandwidth policers, called Access-Network-Location policers. These policers are used exclusively with DEM-GW congestion points (WLGW AP radio). They are similar to existing single bucket policers, but differ in the following aspects:
The policer rate is configured using a ratio (/%) instead of absolute rates.
The ratios are applied against the total estimated measured capacity of the congestion point to derive the actual policer's rate. For example, for measured capacity at congestion time of 1.5Mbps, or a configured policer rate of 30%, the actual policer rate applied:1.5*30% =0.5 Mbps.
Adaptive policers are applied only in the downstream traffic direction.
Adaptive policers run only while the associated ANL is in congestion state. No action is taken when there is no congestion.
These policers are invoked using existing AQP mechanisms that match configured parameters such as apps or app-groups and execute the configured actions.
Adaptive-policers are used to throttle traffic going through access point radios during congestion state. Multiple adapt-policers can be configured per congestion point-type (type =MAC+VLAN). For example:
adapt-policer 1,rate=20(%), backhaul links — called from AQP entry with ‟email” app-group match condition
adapt-policer 2,rate=10(%), backhaul links — called from AQP entry with OTT video app-group match condition
adapt-policer 3,rate=0(%), backhaul links — called from AQP entry with p2p app-group match condition (this effectively drops p2p traffic during congestion)