Method of implementing fast packet flow recognition in high-speed router and firewall

A fast grouping flow identification method in the high-speed router and firewall, including the following steps: creating a root node of decision tree, and assigning the complete-set of rules set in the router or firewall to the root node; recursively dividing the rules set corresponding to each node of decision tree, and when the scale of the rules set of all nodes is smaller than a certain predetermined threshold value, finishing the division; among them, the said division using following method: based on n options for the division to the rules set of nodes, using performance evaluation function ValueP() for each division option, and evaluating and predicting the performance of decision tree generated, and in the generating process of decision tree data structure, the technical program of the invention can evaluate and predict the decision tree balance rate, depth rate, and the occupied space (nodes total number), thereby the generated decision tree has better search time performance under the certain stora