Communication traffic isolation and control systems and methods are disclosed. Communication traffic streams are received and either passed or filtered by respective controllable filtering modules. The operation of the filtering modules is controlled on a per-module and thus a per-stream basis, responsive to congestion of filtered communication traffic streams at a communication traffic processing element to which the filtering modules are connected. Per-stream filtering provides traffic control for each communication traffic stream, and maintains isolation between the streams. Statistics associated with communication traffic filtered out of each stream may be collected, and possibly aggregated.