1. An apparatus for analyzing data streams comprising data packets formed according to a predetermined data transfer protocol, the apparatus comprising: a network transceiver for receiving one or more data streams being conveyed over a network; a bit sequence storage memory array for storing one or more predetermined bit sequences to be recognized in a received data stream; a hardware search engine logic coupled to the network transceiver and with access to the bit sequence storage memory array, for performing a bit-wise comparison of a bit sequence stored in the bit sequence storage memory array with data in the received data stream; a delay buffer, coupled to the network transceiver, having a plurality of outputs for outputting the received data stream with different respective lengths of delay; and a software application coupled to the delay buffer and arranged to receive data packets in the received data stream from one or more of said plurality of outputs, wherein the software application is triggered, in the event that the hardware search engine logic recognizes a stored bit sequence in one or more data packets of a given received data stream, to perform further processing on data packets of the given data stream being output from the delay buffer with a first level of delay, and wherein the software application is further triggered, in dependence upon a result of said further processing, to perform one or more further stages of processing on data packets of the given data stream being output from the delay buffer with one or more levels of delay longer than the first level of delay.