Patent ID: 7197035
Filing Date: 2007-03-27
Classification: H04L

Abstract:
1. A packet transfer apparatus for transferring packets between first and second networks, comprising: an address assignment circuit which assigns a translated network address to a first node belonging to said first network and having a first network address when said packet transfer apparatus transfers a first packet from the first node to a second node belonging to said second network and having a second network address through a connection; an address management circuit which stores for said connection said translated network address, associated with said first and second network addresses; and an address translation circuit which is realized by a dedicated hardware circuit, and translates said first network address contained in a second packet into said translated network address by reference to said address management circuit when said packet transfer apparatus transfers the second packet from said first node to said second node through said connection, and translates said translated network address contained in a third packet into the first network address by reference to said address management circuit when said packet transfer apparatus transfers the third packet from said second node to said first node through said connection, wherein said address management circuit stores at least one reference information item on at least one connection, and each of the at least one reference information item includes a combination of a network address of a node belonging to the first network, a network address of a node belonging to the second network, and a translated network address, said address translation circuit reads in parallel said at least one reference information item from said address management circuit, compares a first predetermined portion of a fourth packet with the at least one reference information item in parallel in order to search for one of the at least one reference information item which matches with the first predetermined portion of the fourth packet, and translates a third network address of a third node belonging to said first network, contained in the fourth packet, into the translated network address included in said one of the at least one reference information item when said fourth packet is transferred from said first network to said second network, or translates a translated network address contained in the fourth packet into the network address of the node belonging to the first network, included in the one of the at least one reference information item, when said fourth packet is transferred from said second network to said first network.