Packet Relay Device And Method For Transferring Packet Therein

• US 20100002703A1
• Filed: 09/14/2009
• Published: 01/07/2010
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kogata, Hiroyuki, Shinohara, Akio
• Granted Patent: US 8,194,561 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags

Abstract

A packet relay device receives an input packet via a first communication port out of a plurality of communication ports of the packet relay device and transmits the input packet via a second communication port out of the plurality of communication ports. The packet relay device includes a learning table storage, a header adder, a discard determiner, and a packet reducer. The learning table storage stores a source address contained in the input packet, in association with an input port identifier capable of identifying the first communication port. The header adder adds an internal transfer header containing the input port identifier to the input packet to generate an internal transfer packet. The discard determiner determines whether to discard the internal transfer packet. The packet reducer reduces the internal transfer packet to preserve at least the source address and the input port identifier upon determining to discard the internal transfer packet.

Claims

1. A packet relay device for receiving an input packet via a first communication port out of a plurality of communication ports of the packet relay device and transmitting the input packet via a second communication port out of the plurality of communication ports, said packet relay device comprising:

a learning table storage for storing a source address contained in the input packet, in association with an input port identifier capable of identifying the first communication port;

a header adder for adding an internal transfer header containing the input port identifier to the input packet to generate an internal transfer packet;

a discard determiner for determining whether to discard the internal transfer packet; and

a packet reducer for reducing the internal transfer packet to preserve at least the source address and the input port identifier upon determining to discard the internal transfer packet.

2. The packet relay device of claim 1, wherein

said input packet is an Ethernet packet containing an MAC header and a payload, and

said source address is an MAC address.

3. The packet relay device of claim 2, wherein

said packet reducer removes a part of the payload from the internal transfer packet to reduce the internal transfer packet.

4. A method for transferring an internal transfer packet within a packet relay device for receiving an input packet via a first communication port out of a plurality of communication ports of the packet relay device and transmitting the input packet via a second communication port out of the plurality of communication ports, said method being executed by the packet relay device, said method comprising:

storing a source address contained in the input packet, in association with an input port identifier capable of identifying the first communication port;

adding an internal transfer header containing the input port identifier to the input packet to generate the internal transfer packet;

determining whether to discard the internal transfer packet; and

reducing the internal transfer packet to preserve at least the source address and the input port identifier upon determining to discard the internal transfer packet.

5. The method of claim 4, wherein

said input packet is an Ethernet packet containing an MAC header and a payload, and

said source address is an MAC address.

6. The method of claim 5, wherein

a part of the payload is removed from the internal transfer packet to reduce the internal transfer packet in the operation of reducing the internal transfer packet.

7. A computer-readable medium storing a program comprising computer-executable instructions enabling a computer to execute a method for transferring an internal transfer packet within the computer, said computer receiving an input packet via a first communication port out of a plurality of communication ports of the computer and transmitting the input packet via a second communication port out of the plurality of communication ports, said method including:

storing a source address contained in the input packet, in association with an input port identifier capable of identifying the first communication port,

adding an internal transfer header containing the input port identifier to the input packet to generate the internal transfer packet,

determining whether to discard the internal transfer packet, and

reducing the internal transfer packet to preserve at least the source address and the input port identifier upon determining to discard the internal transfer packet.

8. The computer-readable medium of claim 7, wherein

said input packet is an Ethernet packet containing an MAC header and a payload, and

said source address is an MAC address.

9. The computer-readable medium of claim 8, wherein

a part of the payload is removed from the internal transfer packet to reduce the internal transfer packet in the operation of reducing the internal transfer packet.