Data packet forwarding method and network device using such method in network address translation mode
AssigneeConnection Technology Systems Inc.
InventorCHANG-WU FU
Life of this patent
Estimating the term…
Abstract
A data packet forwarding method and a network device using such a method in a network address translation mode are provided. The network device includes a central processing unit and a switch chip. The switch chip includes at least a wide area network port and plural local area network ports. The multicast packet is directly forwarded from said wide area network port to corresponding local area network ports. Since the central processing unit is not included in the forwarding path of the multicast packet, the speed of forwarding the multicast packet is enhanced.
Claims18
A data packet forwarding method for use in a network device having a network address translation (NAT) function, said network device comprising a central processing unit (CPU), a switch chip and a forwarding table, said switch chip comprising at least a wide area network port, plural local area network ports, a first connecting port and a second connecting port, said forwarding table storing information associated with a forwarding path of a data packet, said data packet forwarding method comprising steps of:
- segmenting said switch chip into a first virtual local area network terminal and a second virtual local area network terminal with logic segmentation by said central processing unit, wherein said wide area network port and said first connecting port are defined as members belonging to said first virtual local area network terminal, said second connecting port is defined as a member belonging to said second virtual local area network terminal, and said plural local area network ports are defined as members belonging to said first virtual local area network terminal and said second virtual local area network terminal simultaneously;
- receiving said data packet from said wide area network terminal by said wide area network port;
- and
- judging a type of said data packet and forwarding said data packet according to said forwarding table, wherein if said data packet is a multicast packet, said data packet is directly forwarded from said wide area network port to corresponding local area network ports.
A network device for forwarding a data packet from a wide area network terminal to a local area network terminal, said network device comprising:
- a switch chip comprising:
- at least a wide area network port connected to said wide area network terminal;
- plural local area network ports connected to said local area network terminal;
- a first connecting port;
- and
- a second connecting port;
- a forwarding table for storing information associated with a forwarding path of said data packet;
- and
- a central processing unit (CPU) for recording said information associated with said forwarding path of said data packet in said forwarding table, and segmenting said switch chip into a first virtual local area network terminal and a second virtual local area network terminal with logic segmentation according to a network address translation (NAT) function provided by said network device, wherein said wide area network port and said first connecting port are defined as members belonging to said first virtual local area network terminal, said second connecting port is defined as a member belonging to said second virtual local area network terminal, and said plural local area network ports are defined as members belonging to said first virtual local area network terminal and said second virtual local area network terminal simultaneously,
- wherein if said data packet at said wide area network terminal is a multicast packet and said data packet is introduced into said network device through said wide area network port, said data packet is directly forwarded from said wide area network port to corresponding local area network ports by said network device according to said forwarding table.
Dependencies are inferred from the claim text.