A network usage data recording system and method employing an aggregation rule scheme for processing and correlation of network data is described. In one embodiment, the present invention provides a method for recording network usage. The method includes the step of defining a network data collector including an encapsulator, an aggregator and a data storage system. A set of network accounting data is received via the encapsulator. The network accounting data set is converted to a standard data format. The network accounting data set is processed via the aggregator, including the steps of defining a rule chain and applying the rule chain to the network accounting data set to construct an aggregation tree including creating an aggregated network accounting data set. The aggregated network accounting data set is stored in the data storage system.