64 An Efficient Packet Classification Based on the Flow Locality Principles and Multi-Level Lookup

Packet classification is one of key technologies, which is frequently utilized in those network devices, such as routes, firewalls, and so on. In such high-speed network environment, the efficiency and accuracy of packet classification plays a significant role in the development of network. In this paper, we propose an efficient packet classification algorithm based on the flow locality principles and multi-level lookup (PCFM), which can support dynamic update of rule base, achieve high-speed packet classification. The structure of this classification is divided into three levels: The first level is used to store the flow which arrived within 10 seconds, while the second for that arriving between 10 seconds to 60 seconds and the third level for the rest. Experiment results show that PCFM algorithm can reduce the searching time 30% than BFAH while taking the same memory space with comparison to BFAH algorithm.