System and method for translucent bridging

• US 20080080503A1
• Filed: 09/29/2006
• Published: 04/03/2008
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Apisdorf, Joel Z., Shvodian, William M.
• Granted Patent: US 7,916,736 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 12/40091 Bus bridging LAN interconnection over a bridge based backbone H04L12/462; single bridge functionality H04L12/462
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 61/2514 between local and global IP addresses

Abstract

A network bridge (160) is provided, comprising: a local interface (320) configured to transmit and receive local signals in a local network (305); a bridging interface (325) configured to transmit and receive bridging signals in a bridging network (310); a control circuit (330) configured to pass outgoing local data packets from the local network to the bridging network and to pass incoming bridging payloads from the bridging network to the local network; and an address translation circuit (340) configured to provide the control circuit with address translation data identifying a correspondence between local packet addresses and global packet addresses. The control circuit translates outgoing local addresses to outgoing global addresses (460), and the control circuit translates incoming global addresses to incoming local addresses (560), based on the address translation data.

Claims

1. A network bridge, comprising:

a local network interface configured to transmit and receive local signals in a local network according to a local network protocol;

a bridging network interface configured to transmit and receive bridging signals in a bridging network according to a bridging network protocol;

a control circuit connected between the local network interface and the bridging network interface, configured to pass outgoing local data packets from the local network as outgoing bridging payloads in outgoing bridging data packets to the bridging network and to pass incoming bridging payloads from incoming bridging data packets from the bridging network as incoming local packets to the local network; and

an address translation circuit configured to provide the control circuit with address translation data identifying a correspondence between local packet addresses in the local network and global packet addresses,

wherein the control circuit translates outgoing local addresses of the outgoing local data packets to outgoing global addresses based on the address translation data, and

wherein the control circuit translates incoming global addresses of the incoming local data packets to incoming local addresses based on the address translation data.

2. The network bridge of claim 1, further comprising

a memory element connected to the address translation circuit and configured to store address translation information,

wherein the address translation circuit uses the address translation information to generate the address translation data.

3. The network bridge of claim 2,

wherein address translation information comprises a table of corresponding local network address values and global address values,

wherein the incoming local addresses and the outgoing local addresses are local network address values, and

wherein the incoming global addresses and the outgoing global addresses are global network address values.

4. The network bridge of claim 3,

wherein the local network address values comprise ad hoc local network addresses, and

wherein the global addresses comprise unique global addresses assigned to individual devices.

5. The network bridge of claim 1, wherein the local network interface comprises:

a local network physical layer configured to transmit and receive the local signals, to extract the incoming local data packets from received local signals, and to embed the outgoing local data packets into transmitted local signals; and

a local link layer configured to pass the outgoing local data packets from the local network physical layer to the control circuit, and configured pass incoming local data packets from the control circuit to the local network physical layer.

6. The network bridge of claim 1, wherein the bridging network interface comprises:

a bridging network physical layer configured to transmit and receive the bridging signals, to extract the incoming bridging data packets from received bridging signals, and to embed the outgoing bridging data packets into transmitted bridging signals; and

a bridging media access control layer configured to pass the incoming bridging data packets from the bridging network physical layer to the control circuit, and configured pass the outgoing bridging data packets from the control circuit to the bridging network physical layer.

7. The network bridge of claim 1, wherein the network bridge is implemented using one or more integrated circuits.

8. A method of processing a local data packet from a local network through a network bridge, comprising:

receiving the local data packet at the network bridge on a local medium, the local data packet including a local identifier and a local payload;

determining whether the local identifier identifies a destination device selected from one or more known devices that are not in the local network;

translating the local identifier to a global identifier if the local identifier identifies a destination device selected from one or more known devices that are not in the local network;

forming a bridging packet including a local data packet as a bridging payload after translating the local identifier; and

sending the bridging packet over a bridging medium.

9. The method of claim 8, wherein the local and bridging identifiers are both contained within a data link layer.

10. The method of claim 8, further comprising discarding the local data packet if the local identifier does not identify the destination device selected from one or more known devices that are not in the local network.

11. The method of claim 8, further comprising:

determining whether the local identifier identifies the network bridge;

processing the local data packet in the network bridge if the local identifier identifies the network bridge; and

discarding the local data packet if the local identifier does not identify the destination device selected from one or more known devices that are not in the local network and does not identify the network bridge.

12. The method of claim 8, wherein the determining is performed by comparing the local identifier with a plurality of known identifiers stored in a memory device.

13. The method of claim 8, wherein the translating is performed by accessing a table including a plurality of identifier pairs stored in a memory, each of the plurality of identifier pairs including a local device address and a global device address.

14. The method of claim 13,

wherein each of the local device addresses is local address generated by the local network,

wherein each of the global device addresses is either a unique global address, or a bridge-local address pair, and

wherein the bridge-local address pair includes a bridge address identifying a network bridge and a remote address identified by a non-local network.

15. The method of claim 8, wherein the method is implemented using one or more integrated circuits.

16. A method of processing a bridging packet from a bridging network through a local network bridge in a local network, comprising:

receiving the bridging packet at the local network bridge on a bridging medium, the bridging packet containing a local data packet as a bridging payload;

extracting a local data packet from the bridging packet, the local data packet including a global address and a local payload;

determining whether the global identifier identifies a destination device in the local network;

translating the global identifier to a local identifier if the global identifier identifies a destination in the local network; and

sending the local data packet over a local medium after translating the global identifier.

17. The method of claim 16, further comprising discarding the local data packet if the global identifier does not identify the destination device in the local network.

18. The method of claim 16, further comprising:

determining whether the global identifier identifies the network bridge;

processing the local data packet in the network bridge if the global identifier identifies the network bridge; and

discarding the local data packet if the global identifier does not identify the destination device in the local network and does not identify the network bridge.

19. The method of claim 16, wherein the determining is performed by comparing the global identifier with a plurality of known identifiers stored in a memory device.

20. The method of claim 16, wherein the translating is performed by accessing a table including a plurality of identifier pairs stored in a memory, each of the plurality of identifier pairs including a local device address and a global device address.

21. The method of claim 20,

wherein each of the local device addresses is local address generated by the local network, and

wherein each of the global device addresses is either a unique global address, or a bridge-local address pair,

wherein the bridge-local address pair includes a bridge address identifying a network bridge and a remote address identified by a non-local network.

22. The method of claim 16, wherein the method is implemented using one or more integrated circuits.