You can check the rate policies applied to a subscriber in Status->Subscribers. It lists the active subscribers, along with information about their flows and traffic volumes.

Clicking on the [.icon][.icon] chart icon next to the IP address leads to that subscriber statistics metrics. Clicking on the IP address provides detailed information, such as:

You can dig in the active flows of a subscriber in Status->Flows->Per Subscriber, which shows the policy applied to each flow, among other things:

Likewise, given a policy, it is possible to see how many subscriber IP addresses are under each policy going to Status->Policies.

A click on a policy name leads to a list of subscribers using that policy (the ones with more volume consumption will be listed).
