Patent ID: 7600026
Filing Date: 2009-10-06
Classification: H04L

Abstract:
1. An apparatus for Network Address Translation (NAT)/Network Address-Port Translation (NAPT) session management used in a switch controller comprising a packet translation module for performing NAT/NAPT of packets, the switch controller being embodied in hardware, the apparatus comprising: a translation table, which is coupled to the packet translation module, comprising a plurality of storage locations, wherein each storage location is used to store related information of a NAT/NAPT session, and the related information comprises at least an indication, a connection bit, and a connection time; and a control logic, coupled to the packet translation module and the translation table, accessing the related information, and managing the NAT/NAPT session based on the related information; wherein the control logic stores the related information into the translation table, wherein the connection time is equal to a predetermined value of T and the indication shows that the related information is valid, then the control logic increases the connection time by a first value every default unit time and changes the indication to show that the related information is invalid if the connection time reaches a first threshold; wherein an initial value of the connection bit is false, for indicating whether the session is fully established, and in response to a value of the connection bit becoming true, the control logic sets the connection time as a predetermined value of Tlong when the switch controller receives a second packet of the session and SYN, FIN and RST flags of the second packet are not set, a register, which is coupled to and accessed by the control logic, storing the predetermined value T, the unit time, the first value, and the first threshold, and the control logic selecting the predetermined value T, the unit time, the first value and the first threshold based on a protocol which the session uses.