A virtual routing platform includes a line interface a plurality of virtual routing engines (VREs) to identify packets of different packet flows and perform a hierarchy of metering including at least first and second levels of metering on the packet flows. A first level of metering may be performed on...http://www.google.de/patents/US20030223361?utm_source=gb-gplus-sharePatent US20030223361 - System and method for hierarchical metering in a virtual router based network switch
