Abstract: Systems, methods, and other embodiments associated with flexible bit field search are described. According to one embodiment, an apparatus includes a filter configured to receive data packets and a descriptor. The descriptor includes a header and at least one filter descriptor rule. The header identifies a filtering mode. The at least one filter descriptor rule includes instructions that identify a filtering operation in the filtering mode. The filter is also configured to filter the data packets based, at least in part, on the filtering operation identified in the at least one filter descriptor rule.

Abstract: A method and apparatus uses a section filter to perform a filtering operation, such as a match, do not match, within range, or without range filtering operation, on bitstream data in accordance with a rule. The filtering operation may begin at any bit location in the bitstream data and end at any location in the bitstream data. The result of the filtering operation is compared to a value determined by the rule, or if further rules are to be employed, the result is transmitted to a further section filter which performs a further filtering operation on the bitstream data. As many section filters may be linked in this way as the number of rules to be employed. When the section filter corresponding to the last rule to be employed has performed its filtering operation, all results are compared to values determined by the rules employed to determine which data to extract from the bitstream data.