Packet processing apparatus and method

A packet processing method in an ethernet switch system which includes an ethernet switch chip having a routing table and a central processing unit (CPU), the method comprising the steps of:

• at the ethernet switch chip, when the routing table does not have routing information corresponding to an Internet Protocol (IP) address of a destination host of a first packet transmitted from a source host, trapping the packet to the CPU;
• at the CPU, setting imaginary Media Access Control (MAC) address and dummy port information corresponding to the IP address of the destination host of the trapped first packet in the routing table of the ethernet switch, and transmitting an Address Resolution Protocol (ARP) request packet to the IP address of the destination host so as to acquire MAC address and port information of the destination host;
• and
• at the ethernet switch chip, upon receiving a second packet headed for the IP address of the destination host from the source host before an ARP response packet is received in accordance with the ARP request packet and before the routing information corresponding to the IP address of the destination host is acquired, switching the second packet to a dummy port set in the routing table of the ethernet switch chip without trapping the packet to the CPU.

A packet processing apparatus of an ethernet switching system, comprising:

• an ethernet switch for trapping a first packet transmitted from a source host to a central processing unit (CPU) when a routing table does not have routing information corresponding to an Internet Protocol (IP) address of a destination host;
• and
• an Address Resolution Protocol (ARP) processor for setting an imaginary Media Access Control (MAC) address and dummy port information corresponding to the IP address of the destination host in the routing table of the ethernet switch, and for transmitting an ARP request packet to the IP address of the destination host so as to acquire MAC address and port information of the destination host,
• wherein the ethernet switch, upon receipt of a second packet headed for the IP address II of the destination host from the source host before an ARP response packet is received in accordance with the ARP request packet and before the routing information corresponding to the IP address of the destination host is acquired, switches the second packet to a dummy port set in the routing table of the ethernet switch chip without trapping the packet to the CPU.