Abstract: A method for packet filtering in a network switch includes: utilizing an access control list circuit to filter received packets, wherein the access control list circuit compares header information of the received packets with an access control list to filter the received packets, where the access control list has at least one entry, and rule information in the entry includes only a portion of an IP address; and utilizing a routing circuit to further filter packets that pass the access control list circuit, wherein the routing circuit compares header information of the packets that pass the access control list circuit with a routing table to filter the packets, wherein the routing table has at least one entry, and rule information in the entry includes an entire IP address.

Abstract: A network switch is configured to receive packet data. The network switch includes a memory and a processor. The memory is configured to store an access control list and an abnormity detecting program, filter the packet data according to the access control list, and perform an abnormity detecting procedure on the packet data according to the abnormity detecting program. When at least one abnormity event occurs in one of a plurality of time intervals, a counting value increases. When the counting value reaches a counting threshold value, the memory sends an abnormity notification to the processor and the processor performs an abnormity processing procedure on the packet data.

Abstract: A method for packet filtering in a network switch includes: utilizing an access control list circuit to filter received packets, wherein the access control list circuit compares header information of the received packets with an access control list to filter the received packets, where the access control list has at least one entry, and rule information in the entry includes only a portion of an IP address; and utilizing a routing circuit to further filter packets that pass the access control list circuit, wherein the routing circuit compares header information of the packets that pass the access control list circuit with a routing table to filter the packets, wherein the routing table has at least one entry, and rule information in the entry includes an entire IP address.