US Patent 7508825 Data packet classification

This specification describes technologies relating to classifying data packets based on general property ranges. An interval tree is constructed to represent the applicability of rules to non-overlapping ranges of a data classification property. The interval tree can be a binary tree such as a balanced binary tree or red-black tree. To determine which rules apply to a data packet, the data packet property is compared to the intervals in the tree to find a match. To balance the time and space complexity, a heuristics based approach is used for classifying data packets based on general property ranges of more than one data classification property.