Abstract: Incoming data packets are often processed according to their origination or destination port. In order to efficiently determine applicable rules based on port values, ranges are stored in association with corresponding rules in a ternary memory. In order to reduce the amount of required memory to store these ranges, extra unused bits of the ACL that includes the rule can be used. Further, to maximize the storage capability of these limited extra bits, most common ranges can be stored in one or more bit partitions depending on whether they encompass other most common ranges to be stored in the extra bits. Through partitioning and intelligent bit assignment, many ranges can be stored in the limited extra bits, and can each remain individually addressable.

Abstract: Incoming data packets are often processed according to their origination or destination port. In order to efficiently determine applicable rules based on port values, ranges are stored in association with corresponding rules in a ternary memory. In order to reduce the amount of required memory to store these ranges, extra unused bits of the ACL that includes the rule can be used. Further, to maximize the storage capability of these limited extra bits, most common ranges can be stored in one or more bit partitions depending on whether they encompass other most common ranges to be stored in the extra bits. Through partitioning and intelligent bit assignment, many ranges can be stored in the limited extra bits, and can each remain individually addressable.

Abstract: A method and apparatus for ordering a plurality (P) of entries having various prefix lengths for storage in a number (T) of available storage locations in a content addressable memory (CAM) array according to the prefix lengths is disclosed. Initially, a first number (N) of the entries of selected and used to generate a distribution graph of their prefix lengths. Then, for each unique prefix length, a corresponding subset of the T storage locations in the CAM array are allocated according to a predicted prefix length distribution indicated by the distribution graph. Then, all of the entries are stored in the corresponding allocated storage locations according to prefix length.

Abstract: A method and apparatus for ordering a plurality (P) of entries having various prefix lengths for storage in a number (T) of available storage locations in a content addressable memory (CAM) array according to the prefix lengths is disclosed. Initially, a first number (N) of the entries of selected and used to generate a distribution graph of their prefix lengths. Then, for each unique prefix length, a corresponding subset of the T storage locations in the CAM array are allocated according to a predicted prefix length distribution indicated by the distribution graph. Then, all of the entries are stored in the corresponding allocated storage locations according to prefix length.