Classifying Packets with Hierarchical Intelligent Cuttings

Increasing demands on Internet router performance and functionality create a need for algorithms that classify packets quickly with minimal storage requirements and allow frequent updates. Unlike previous algorithms, the algorithm proposed here meets this need well by using heuristics that exploit structure present in classifiers. Our approach, which we call HiCuts (hierarchical intelligent cuttings), attempts to partition the search space in each dimension, guided by simple heuristics that exploit the classifier's structure. We discover this structure by preprocessing the classifier. We can tune the algorithm's parameters to trade off query time against storage requirements. In classifying packets based on four header fields, HiCuts performs quickly and requires relatively little storage compared with previously described algorithms.