Port within a multi-port bridge including a buffer for storing routing information for data packets received in the port

• US 6,751,225 B1
• Filed: 03/19/1999
• Issued: 06/15/2004
• Est. Priority Date: 09/17/1997
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Chung, David
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): George, Keith M.
• Application Number:
  US09/272,846
• Time in Patent Office: 1,915 Days
• Field of Search: 370/389, 370/401, 370/402, 370/412, 370/413, 370/417, 370/419, 370/423, 370/428, 370/429, 370/392
• US Class Current: 370/401
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/40013 Details regarding a bus controller
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/42 Loop networks
• CPC Class Codes: H04L 12/462 LAN interconnection over a bridge based backbone
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/135 by jamming the transmission media
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 49/102 using shared medium, e.g. bus or ring
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 49/354 for supporting virtual local area networks [VLAN]
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04L 49/9057 Arrangements for supporting packet reassembly or resequencing
• CPC Class Codes: H04L 49/9073 Early interruption upon arrival of a fraction of a packet
• CPC Class Codes: H04L 49/9089 replacing packets in a storage arrangement, e.g. pushout

Abstract

The invention is a port in a multi-port bridge for a local area network having a vector buffer for storing vectors relating to the routing of data packets received in the port. The bridge includes a plurality of ports coupled a data bus and to a look-up bus. A look-up table coupled to the look-up bus correlates destination node addresses from each packet to an appropriate destination port. In addition, a packet buffer is coupled to the data bus for temporarily storing data packets. When a packet is received into a receive buffer of a source port, a destination and source address included in the packet are utilized to update the look-up table and to identify the appropriate destination port for the packet. This is preferably performed by the source port communicating with the look-up table via the look-up bus. Once the destination port has been identified, the identification of the destination port is stored in the receive vector for the packet. While a data packet is being communicated to the destination port via the data bus, appropriate destination ports can be identified for additional data packets received in the port. Accordingly, an advantage of the present invention is that operations for multiple data packets received by the port can be performed simultaneously, thus, increasing the packet handling capacity of the multi-port bridge.

Claims

1. A method of directing data packets through a multi-port bridge for a local area network, the method comprising:

a. receiving a first data packet in a receive buffer of a port of the multi-port bridge;

b. initializing a vector for the first data packet in a vector buffer of the port wherein the vector is for storing information relating to the routing of the first data packet through the multi-port bridge;

c. obtaining an identification of a destination port for the first data packet and storing the identification of the destination port for the first data packet in the vector for the first data packet;

d. receiving a second data packet in the receive buffer after receiving the first data packet in the receive buffer;

e. initializing a vector for the second data packet in the vector buffer of the port wherein the vector for the second data packet is for storing information relating to the routing of the second data packet through the multi-port bridge;

f. obtaining an identification of a destination port for the second data packet; and

storing the identification of the destination port for the second data packet in the vector for the second packet; and

g. forwarding the first data packet to the destination port for the first data packet, wherein obtaining the identification of the destination port for the second data packet is performed during performance of forwarding the first data packet to the destination port.

2. A method of directing data packets through a multi-port bridge for a local area network, the method comprising:

a. receiving a first data packet in a receive buffer of a port of the multi-port bridge;

b. initializing a vector for the first data packet in a vector buffer of the port wherein the vector is for storing information relating to the routing of the first data packet through the multi-port bridge;

c. obtaining an identification of a destination port for the first data packet and storing the identification of the destination port for the first data packet in the vector for the first data packet;

d. receiving a second data packet in the receive buffer after receiving the first data packet in the receive buffer;

e. initializing a vector for the second data packet in the vector buffer of the port wherein the vector for the second data packet is for storing information relating to the routing of the second data packet through the multi-port bridge;

f. obtaining an identification of a destination port for the second data packet; and

storing the identification of the destination port for the second data packet in the vector for the second packet; and

g. forwarding the first data packet to the destination port for the first data packet, wherein forwarding the first data packet to the destination port for the first data packet is performed via a data bus coupled to the port and wherein obtaining the identification of the destination port for the second packet is performed via a look-up bus coupled to the port.

3. A multi-port bridge for interconnecting a plurality of segments of a local area network (LAN), the multi-port bridge comprising a port, wherein the port comprises:

a. a receive buffer to temporarily store a plurality of data packets received by the port from a segment of the LAN;

b. a vector buffer to store a vector corresponding to each data packet stored by the receive buffer wherein each vector is to store information relating to routing of the corresponding data packet through the multi-port bridge, wherein an identification of a destination port for a first data packet of the plurality is stored in the vector corresponding to the first data packet; and

c. a data bus coupled to the receive buffer to forward the first data packet to the destination port for the first data packet;

wherein a second data packet of the plurality is received by the port after the first data packet is received by the port and wherein an identification of a destination port for the second data packet is obtained while the first data packet is being forwarded to the destination port for the first data packet.

4. The multi-port bridge according to claim 3 further comprising a look-up bus coupled to the vector buffer to communicate the identification of the destination port for the second packet to the port.

5. The multi-port bridge according to claim 4 further comprising a look-up table coupled to the look-up bus wherein the look-up table correlates a destination address from the second packet to the identification of the destination port for the second packet.

6. The multi-port bridge according to claim 5 wherein the destination address from the second packet is communicated to the look-up table via the look-up bus.

7. An apparatus for interconnecting a plurality of segments of a local area network (LAN), the apparatus comprising a port, the port comprising:

a. first storage means for storing a plurality of data packets received from a segment of the LAN;

b. second storage means for storing information relating to routing of a corresponding data packet through the apparatus, wherein an identification of a destination port for a first data packet of the plurality is stored in the second storage means, and further wherein a second data packet of the plurality is received by the port after the first data packet is received by the port and wherein an identification of a destination port for the second data packet is stored in the second storage means after the identification of the destination port for the first packet is stored in the second storage means;

c. means coupled to the first storage means for communicating the first data packet to the destination port for the first data packet; and

d. means coupled to the second storage means for identifying the destination port for the second packet;

wherein the means for communicating the first data packet to the destination port and the means for identifying the destination port for the second packet are simultaneously operable.

8. A multi-port bridge for interconnecting a plurality of segments of a local area network (LAN) wherein each segment includes one or more nodes, the multi-port bridge comprising:

a. a first port coupled to a first segment of the LAN wherein the first port comprises;

i) a receive buffer for storing a plurality of data packets received from the corresponding segment of the LAN wherein each data packet includes a node address of a destination node for the data packet; and

ii) a vector buffer for storing a vector corresponding to each data packet stored by the receive buffer wherein each vector is for storing an identification of a destination port for the corresponding data packet;

b. a second port coupled to a second segment of the LAN, wherein the second segment of the LAN includes the destination node for a first packet of the plurality and wherein a first vector corresponding to the first packet stores an identification of the second segment of the LAN and further wherein the second port is identified as the destination port for the first data packet by looking up a destination node address from the first data packet in a look-up table and wherein the look-up table correlates destination node addresses to identifications of destination ports; and

c. a data bus coupled to the first port and to the second port for communicating the data packets, wherein a destination port for a second data packet received by the first port is obtained from the look-up table while the first data packet is communicated to the second port via the data bus.

9. The multi-port bridge according to claim 8 further comprising a look-up bus coupled to the first port, to the second port and to the look-up table.

10. A multi-port bridge for interconnecting a plurality of segments of a local area network (LAN) wherein each segment includes one or more nodes, the multi-port bridge comprising:

a. a first port coupled to a first segment of the LAN wherein the first port comprises;

i) a receive buffer for storing a plurality of data packets received from the corresponding segment of the LAN wherein each data packet includes a node address of a destination node for the data packet; and

ii) a vector buffer for storing a vector corresponding to each data packet stored by the receive buffer wherein each vector is for storing an identification of a destination port for the corresponding data packet;

b. a second port coupled to a second segment of the LAN, wherein the second segment of the LAN includes the destination node for a first packet of the plurality and wherein a first vector corresponding to the first packet stores an identification of the second segment of the LAN and further wherein the second port is identified as the destination port for the first data packet by looking up a destination node address from the first data packet in a look-up table and wherein the look-up table correlates destination node addresses to identifications of destination ports; and

c. a data bus coupled to the first port and to the second port for communicating the data packets, wherein the look-up table is updated in response to the second packet while the first packet is communicated to the second port via the data bus.

11. The multi-port bridge according to claim 10 further comprising a look-up bus coupled to the first port, to the second port and to the look-up table.