Patent ID: 8091136

Claim:
A packet transfer apparatus for performing transfer of a packet that is received via a communication network, comprising: a plurality of network interfaces; a storage unit configured to store at least a predetermined search pattern that is data for identifying an attack target apparatus and an Ethernet address identifying a harmful packet removal apparatus; a determination unit configured to determine whether predetermined harmful packet removal data in a packet received from a network interface matches the search pattern; an output interface determination unit configured to determine a network interface for outputting the packet based on the determination result by the determination unit and the network interface from which the packet is received; an address replacement unit configured to replace an Ethernet address identifying a destination apparatus of the packet with an Ethernet address identifying the harmful packet removal apparatus when outputting the packet from a network interface connected to the harmful packet removal apparatus; and a packet sending unit configured to send the packet to the network interface determined by the output interface determination unit.