Method and apparatus for packet processing

An apparatus for packet processing, comprising:

• a packet parser configured to receive and parse packets and forward a parsed packet to a key constructor;
• the key constructor configured to map information contained with the parsed packet to a group of parameter ranges in a plurality of configurations, each parameter range including a plurality of parameter fields having upper and lower limits of the parameter range and to construct a search key based on parameters of the parsed packet and indications of ranges among a group of ranges within which a parameter of the parsed packet belongs;
• a comparator configured to select a port number within one of the parameter ranges and compare the selected port number with the upper and lower limits to determine that the selected port number belongs to the one of the parameter ranges;
• a rule tester coupled to the key constructor, the rule tester being configured to determine that the search key satisfies a rule, the rule including a field, a position of a bit in the field is configured to indicate one of the configurations that is required by the rule;
• and
• a packet handler coupled to the rule tester, the packet handler being configured to receive an unparsed packet, and to execute an action associated with the rule on the unparsed packet.

A packet switching device, comprising:

• an interface coupled to an outer link, the interface being configured to receive a packet from the outer link;
• and
• a packet processor coupled to the interface to process the packet, the packet processor being configured to further comprise:
• a packet parser configured to receive and parse the packet and forward a parsed packet to a key constructor;
• the key constructor configured to map information contained with the parsed packet to a group of parameter ranges in a plurality of configurations, each parameter range including a plurality of parameter fields having upper and lower limits of the parameter range and to construct a search key based on parameters of the parsed packet and indications of ranges among a group of ranges within which a parameter of the parsed packet belongs;
• a comparator configured to select a port number within one of the parameter ranges and compare the selected port number with the upper and lower limits to determine that the selected port number belongs to the one of the parameter ranges;
• a rule tester coupled to the key constructor, the rule tester being configured to determine a rule that the search key satisfies the determined rule, the rule including a field, a position of a bit in the field is configured to indicate one of the configurations that is required by the rule;
• and
• a packet handler coupled to the rule tester, the packet handler being configured to receive an unparsed packet, and execute an action associated with the determined rule on the unparsed packet.