Patent ID: 8902756
Filing Date: 2014-12-02
Classification: H04L

Abstract:
1. A packet transfer processing device comprising: a search table that includes a plurality of entry areas to store a plurality of packet search conditions; a search processing unit that, whenever a packet is received, compares a communication parameter of the received packet with the plurality of packet search conditions stored in the search table and outputs a search result corresponding to a packet search condition matching the communication parameter; a transfer processing unit that executes processing for transferring or dropping the received packet based on the search result; a validity management table that stores information for setting whether each packet search condition is valid or invalid, in association with each of the plurality of packet search conditions stored in the search table; timers that correspond to the plurality of entry areas; a timer managing unit that starts a counting operation by a timer whenever a packet in which a communication parameter matches a packet search condition corresponding to information on the validity management table that is set as valid is received or whenever the information is written in the validity management table; a time-out management table that stores information indicating whether the timer is performing the counting operation or times out, for each timer; a validity/invalidity managing unit that stores information indicating that the timer times out in the time-out management table and changes information corresponding to the timed-out timer among the information stored in the validity management table from validity to invalidity if a counting time of the timer exceeds a preset time-out time; and a control unit that, when the communication starts, detects an empty entry area of the search table based on the information stored in the time-out management table and stores a packet search condition needed to perform the communication in the detected empty entry area.