Patent ID: 6615336
Filing Date: 2003-09-02
Classification: H04L

Abstract:
A memory structure for storing a forwarding table in a memory of a network switch of an Ethernet network so as to facilitate a medium access control (MAC) address lookup in the network switch, the memory structure comprising:a plurality of multi-slot buckets, wherein each of the multi-slot buckets is mapped to a hash key which is formed by partial bits in a MAC address that is used for data transmission, wherein each of the multi-slot buckets comprises: a first forwarding table section for storing a first forwarding table entry and a second forwarding table entry; a second forwarding table section for storing a third forwarding table entry and a fourth forwarding table entry; and a third forwarding table section for storing port masks associated with the first, second, third, and fourth forwarding table entries; wherein the first, second, third, and fourth forwarding table entries each have respective data fields for MAC content, source port, and static flag, excluding the associated port masks; wherein the first, second, and third forwarding table sections are separately read from the multi-slot bucket in a burst mode via a data bus whose bus width is less than a data length of each of the first, second, and third forwarding table sections; wherein the port masks stored in the third forwarding table section are read from the multi-slot bucket only when the data transmission is multicast; and whereby the MAC address lookup is completed within at most three times of reading the memory of the network switch.