1. A network device for processing data on a data network, the network device comprising: a plurality of ports, configured to receive data packets and to send out processed data packets; a modification engine, in communication with the plurality of ports, configured to parse, evaluate and modify the data packets to produce the processed data packets; and a series of search engine pipeline stages, in communication with the modification engine, configured to perform lookup searches through a plurality of search engines; wherein the series of search engine pipeline stages perform search requests in sequential processing steps and any stage of the series of search engine pipeline stages may submit a particular search request to the plurality of search engines and receive search results particular to a particular data packet at a respective processing step.