Connecting multi-hop mesh networks using MAC bridge

• US 8,340,106 B2
• Filed: 03/13/2006
• Issued: 12/25/2012
• Est. Priority Date: 03/13/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Sapek, Adam, Venketesan, Thiruvengadam
• Primary Examiner(s): Blanton, John
• Assistant Examiner(s): TRAN, THINH D
• Application Number:
  US11/375,292
• Publication Number:
  US 20070211736A1
• Time in Patent Office: 2,479 Days
• Field of Search: 370/401, 370/85
• US Class Current: 370/401
• CPC Class Codes: H04L 12/462 LAN interconnection over a bridge based backbone
• 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

Abstract

A multi-hop mesh network may be connected to a Local Area Network (LAN) using a MAC Bridge. One or more nodes on the mesh network may be configured as a bridge node that employs a MAC bridge. Packets that travel between stations on the LAN to nodes on the mesh network flow through one of the bridge nodes on the mesh network. The bridge nodes do not receive all the packets on mesh network, but they receive the packets that are to be transmitted across the MAC bridge. As the bridge nodes learn of new stations on the LAN they advertise routes to the other nodes within the mesh network specifying how to reach those stations. This enables MAC Bridge functionality between wireless mesh networks and 802 LANs.

Claims

1. A computer-implemented method for connecting a mesh network to a LAN using a standard MAC Bridge, comprising:

determining addresses of stations on the LAN using a bridge node;

wherein the bridge node comprises a mesh driver that is located between a MAC bridge layer and a wireless adapter that is coupled wirelessly to the mesh network;

wherein upon receiving a packet at the wireless adapter from the mesh network, the mesh driver;

checks an address of the packet;

determines when the address is a local node on the mesh network without accessing the MAC Bridger layer;

determines when the address is not an address of a local node and only when the address is not the address of the local node on the mesh network then the mesh driver moves the packet up to the MAC Bridge layer and stores the address as a LAN station within a list of non-mesh neighbors that have communicated with the bridge node and removing one of the stations from the list when the bridge node has not received any packets that are associated with the one of the stations for a predetermined period of time;

proactively advertising each of the determined addresses of the LAN stations to other nodes within the mesh network comprising non-bridge nodes as being a mesh neighbor of the bridge node regardless of the need for a route; and

directing packets from nodes on the mesh network destined to stations on the LAN through the bridge node.

2. The method of claim 1, wherein determining the addresses of stations on the LAN using a bridge node comprises examining addresses associated with a packet sent to the mesh network from the bridge node.

3. The method of claim 2, wherein a source address associated with the packet is identified as an address of a station on the LAN when the address is not a local address of the bridge node.

4. The method of claim 3, wherein the list is updated when a new LAN station is determined.

5. The method of claim 4, further comprising the bridge node advertising to other nodes on the mesh network mesh routes that can be used to reach the LAN stations within the list.

6. The method of claim 4, further comprising bridge node advertising the LAN stations within the list as neighbors of the bridge node.

7. The method of claim 6, further comprising marking the neighbors as special neighbors not on the mesh but reachable through the bridge node.

8. A computer-readable memory having computer executable instructions for connecting a mesh network to a LAN using a standard MAC Bridge, comprising:

determining addresses of stations on the LAN from the mesh network;

proactively advertising each of the determined addresses of the LAN stations to other nodes within the mesh network comprising non-bridge nodes as being a mesh neighbor of a bridge node on the mesh network;

wherein the advertisement is performed using a proactive mesh routing protocol such that the advertisement occurs regardless of whether or not a need for a route exists, and

directing packets from nodes on the mesh network destined to stations on the LAN through a bridge node on the mesh network;

wherein the bridge node comprises a mesh driver that is located between a MAC bridge layer and a wireless adapter that is coupled wirelessly to the mesh network;

wherein upon receiving a packet from the mesh network, the mesh driver checks an address of the packet and when the address is not an address of a local node on the mesh network, only then the mesh driver moves the packet up to the MAC Bridge layer and otherwise not moving the packet up to the MAC Bridge layer and not accessing MAC bridge layer when the address is an address of a local node on the mesh network and storing the address as a LAN station within a list of non-mesh neighbors that have communicated with the bridge node and removing one of the stations from the list when the bridge node has not received any packets that are associated with the one of the stations for a predetermined period of time.

9. The computer-readable memory of claim 8, wherein determining the addresses of stations on the LAN from the mesh network comprises examining addresses associated with a packet sent to the mesh network.

10. The computer-readable memory of claim 9, wherein a source address associated with the packet is identified as an address of a station on the LAN when the address is not a local address of the bridge node.

11. The computer-readable memory of claim 10, wherein the list is updated when a new LAN station is determined.

12. The computer-readable memory of claim 11, further comprising advertising to other nodes on the mesh network mesh routes that can be used to reach the LAN stations within the list.

13. The computer-readable memory of claim 11, further comprising advertising the LAN stations within the list as neighbors of the bridge node.

14. The computer-readable memory of claim 13, further comprising marking the neighbors on the LAN as special neighbors as not on the mesh but reachable through the bridge node.

15. An apparatus for connecting a mesh network to a LAN using a standard MAC Bridge, comprising:

a processor and a computer-readable storage medium;

an operating environment stored on the computer-readable storage medium and executing on the processor and that is configured to interact with;

a standard MAC bridge;

a LAN adapter driver that is coupled to the MAC bridge and that is coupled to the LAN; and

a mesh driver that is coupled to the MAC bridge and that is coupled to a mesh adapter driver that is connected to the mesh network;

directing packets from nodes on the mesh network destined to stations on the LAN through a bridge node on the mesh network;

wherein the mesh driver that is located between the MAC bridge prevents local packets from being moved to the MAC bridge and a wireless adapter that is coupled wirelessly to the mesh network; and

wherein the mesh driver is configured to determine addresses of stations on the LAN;

use functionality of the MAC bridge only when an address is non-local, proactively advertise each of the determined addresses of the LAN stations to other nodes within the mesh network comprising non-bridge nodes as being a mesh neighbor of the apparatus regardless of a need for a route; and

direct packets from nodes on the mesh network destined to stations on the LAN and store the address as a LAN station within a list of non-mesh neighbors that have communicated with the bridge node and updating the list after the passing of a predetermined period of time.

16. The apparatus of claim 15, wherein determining the addresses of stations on the LAN from the mesh network comprises examining addresses associated with a packet sent to the mesh network.

17. The apparatus of claim 16, wherein a source address associated with the packet is identified as an address of a station on the LAN when the address is not a local address of the bridge node.

18. The apparatus of claim 17, wherein the list is updated when a new LAN station is determined.

19. The apparatus of claim 18, further comprising performing at least one of:

advertising to other nodes on the mesh network mesh routes that can be used to reach the LAN stations within the list and advertising the LAN stations within the list as neighbors of the bridge node.

20. The apparatus of claim 19, further comprising marking the neighbors on the LAN as special neighbors as not on the mesh.