摘要 |
A classification search engine for the application of classification rules to a data packet comprises a rules engine for applying a succession of rules, each rule including an operating code. At least some rules are each a single rule of which the operating code specifies a respective portion of the packet, such as a longword, for the extraction of data for the application of the respective rule. Each single rule includes a mask field for controlling the application of the single rule to the data. Other rules are multiple rules of which the operating codes identifies the rule as a multiple rule and which includes a mask for controlling the application of the multiple rule to the results of the application of a multiplicity of single rules to the packet. The operating code for a single rule specifies a pre-determined packet type and a decoder will determine whether a packet conforms to this type (which may be specific or generic) before allowing the application of the rule to the packet. |