Multi-radio mesh network system supporting at least two different wireless communication standards and method of controlling the same

• US 20080080430A1
• Filed: 09/17/2007
• Published: 04/03/2008
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Yong, Choi, Wook, Choi, Hyo-Hyun, Park, Yong-Seok
• Granted Patent: US 7,978,657 B2
• Time in Patent Office: Days
• US Class Current: 370/332
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

In a multi-radio mesh network system supporting at least two different wireless communication standards and a method of controlling the same, a wireless access switching module determines whether user data en-queued in the queue of a first wireless link and retained on standby cannot be transmitted. The wireless access switching module switches the user data, en-queued in the queue of the first wireless link and retained on standby, to an available second wireless link. The wireless access switching module changes a frame structure according to different wireless access techniques. When access is possible through the second wireless link, a forwarder searches for a local neighbor directly connected to a transmitting node and a receiving node, and forwards the user data. According to the invention, and in contrast to conventional techniques, available multi-wireless resources can be used more efficiently, flexibly and optimally up to the last moment, thereby reducing re-transmission and packet drop. Thus, each hop supports fast data forwarding so as to improve network performance.

Claims

1. A method of controlling a multi-radio mesh network system supporting at least two different wireless communication standards, the method comprising the steps of:

(a) determining, at a wireless access switching module, whether user data en-queued in a queue of a first wireless link and retained on standby cannot be transmitted;

(b) switching, at the wireless access switching module, the user data en-queued in the queue of the first wireless link and retained on standby to an available second wireless link when it is determined, in step (a), that the data en-queued in the queue of the first wireless link and retained on standby cannot be transmitted;

(c) changing, at the wireless access switching module, a frame structure according to different wireless access techniques; and

(d) when access is possible through the second wireless link, searching at a forwarder for a local neighbor directly connected to a transmitting node and a receiving node, and forwarding the user data.

2. The method of claim 1, further comprising the steps of:

providing neighbor information to a neighboring node; and

generating a neighbor table based on neighbor information received from the neighboring node.

3. The method of claim 2, wherein the neighbor information comprises information on each wireless link established through a corresponding node.

4. The method of claim 2, further comprising the step of:

generating, at a multi-wireless-path selector, a forwarding information base (FIB) with reference to the neighbor table.

5. The method of claim 4, wherein the FIB includes destination information of the user data and neighbor information of a same wireless link.

6. The method of claim 2, wherein the step (b) of switching the user data to an available second wireless link comprises the steps of:

(b1) searching, at the wireless access switching module, a forwarding information base (FIB) generated by a multi-radio path selector, and selecting a wireless link for transmitting the user data;

(b2) attempting, at the wireless access switching module, to transmit the user data through the selected wireless link, and determining whether there is a fault in the wireless link; and

(b3) when it is determined in step (b2) that there is a fault in the wireless link, re-searching, at the wireless access switching module, the FIB, checking a next wireless link, and then switching to an existing wireless link.

7. The method of claim 2, wherein, in step (d) of searching at a forwarder for a local neighbor directly connected to the transmitting node and the receiving node and forwarding the user data, the user data is forwarded through a common neighbor to which the transmitting node and the receiving node are connected in common when there is no local neighbor.

8. The method of claim 1, wherein, in step (c) of changing, at the wireless access switching module, the frame structure according to different wireless access techniques, only a corresponding frame among the user data en-queued in the queue of the first wireless link in which a fault has occurred is de-queued and re-queued in the second wireless link.

9. The method of claim 1, wherein, in step (c) of changing, at the wireless access switching module, a frame structure according to different wireless access techniques, all of the user data en-queued in the first wireless link in which a fault has occurred is de-queued and re-queued in the second wireless link.

10. The method of claim 9, wherein step (c) comprises performing a change in an upper media access control (MAC) layer.

11. The method of claim 8, wherein step (c) comprises performing a change in an upper media access control (MAC) layer.

12. A multi-radio mesh network system supporting at least two different wireless communication standards, the system comprising:

a wireless access switching module which, when a first wireless link for transmitting user data is down or a fault has occurred for some reason in the first wireless link so that the user data cannot be transmitted, switches the user data en-queued in a queue of the first wireless link and retained on standby to an available second wireless link;

a de-queue processor for de-queuing only a corresponding frame among the user data en-queued in the queue of the first wireless link in which a fault has occurred, and re-queuing the frame in the available second wireless link; and

a forwarder which, when access is possible through the available second wireless link, searches for a local neighbor directly connected to a transmitting node and a receiving node, and forwards the user data.

13. The multi-radio mesh network system of claim 12, further comprising:

a neighbor provider for providing neighbor information to a neighboring node; and

a neighbor generator for generating a neighbor table based on the neighbor information received from the neighboring node.

14. The multi-radio mesh network system of claim 13, wherein the neighbor information includes information on each wireless link established through a corresponding node.

15. The multi-radio mesh network system of claim 13, further comprising a multi-wireless-path selector for generating a forwarding information base (FIB) with reference to the neighbor table.

16. The multi-radio mesh network system of claim 15, wherein the FIB includes destination information of the user data and neighbor information comprising a same wireless link.

17. The multi-radio mesh network system of claim 13, wherein the wireless access switching module searches a forwarding information base (FIB) generated by a multi-wireless-path selector, and selects a wireless link for the forwarder to use in transmitting the user data, attempts to transmit the user data through the selected wireless link, determines whether there is a fault in the wireless link, and when a fault occurs in the wireless link, re-searches the FIB, checks a next wireless link, and then switches to an existing wireless link.

18. The multi-radio mesh network system of claim 12, further comprising a data converter which, when the wireless access switching module switches between different wireless access techniques, changes a frame structure.

19. The multi-radio mesh network system of claim 18, wherein the data converter de-queues all of the user data en-queued in the first wireless link in which a fault has occurred, and re-queues the user data in the second wireless link.

20. The multi-radio mesh network system of claim 19, wherein the change of frame structure is performed in an upper media access control (MAC) layer.

21. The multi-radio mesh network system of claim 18, wherein the change of frame structure is performed in an upper media access control (MAC) layer.

22. The multi-radio mesh network system of claim 13, wherein, when there is no local neighbor, the forwarder forwards the user data through a common neighbor to which the transmitting node and the receiving node are connected in common.