Mesh network that includes fixed and mobile access nodes

• US 20060114881A1
• Filed: 01/18/2006
• Published: 06/01/2006
• Est. Priority Date: 12/29/2000
• Status: Active Grant

• Current Assignee: Hitachi Energy Switzerland AG (Hitachi, Ltd.)
• Original Assignee: Tropos Networks Incorporated (ABB Limited)
• Inventors: Srikrishna, Devabhaktuni, Chari, Amalavoyal
• Granted Patent: US 7,697,504 B2
• Time in Patent Office: Days
• US Class Current: 370/351
• CPC Class Codes: H04L 45/125 based on throughput or bandwidth
• CPC Class Codes: H04L 45/20 Hop count for routing purposes, e.g. TTL
• CPC Class Codes: H04W 40/12 based on transmission quality or channel quality
• CPC Class Codes: H04W 40/22 using selective relaying for reaching a BTS [Base Transceiver Station] or an access point
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 40/30 for proactive routing
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

An apparatus and method of selecting a routing path through a mesh network that includes a mobile access node is disclosed. The method includes each access node of the mesh network capable of receiving routing beacons from at least one upstream access node. The routing beacons including information of all upstream access nodes along a path to a gateway access node. The mobile access node selecting a route through an upstream access node based upon a quality of beacons received from at least one upstream access node, and whether the at least one upstream access node is a fixed access node or another mobile access node.

Claims

1. A method of selecting a routing path through a mesh network that includes a mobile access node, comprising:

each access node of the mesh network capable of receiving routing beacons from at least one upstream access node, the routing beacons including information of upstream access nodes along a path to a gateway access node;

the mobile access node selecting a route through an upstream access node based upon;

a) a quality of beacons received from at least one upstream access node, and

b) whether the at least one upstream access node is a fixed access node or another mobile access node.

2. The method of claim 1, wherein the information comprises addresses of all upstream access nodes along the path to the gateway access node.

3. The method of claim 1, wherein the routing beacons originate at gateway access nodes.

4. The method of claim 1, further comprising each access node that receives routing beacons, modifying the routing beacons of a selected route by attaching an address of the access node, and re-broadcasting the modified beacons.

5. The method of claim 1, wherein the quality of beacons is determined by a percentage of routing packets per unit of time transmitted from the upstream node that are received from the upstream access node.

6. The method of claim 1, wherein the quality of beacons is determined by at least one an SNR of the beacons received by the access node, or a PER of beacons received by the access node

7. The method of claim 1, further comprising the mobile access node determining a reverse link quality between the mobile access node and the at least one upstream access node.

8. The method of claim 7, wherein the route selection by the mobile access node is additionally based upon the reverse link quality between the mobile access node and the at least one upstream access node.

9. The method of claim 1, further comprising fixed access nodes of the mesh network selecting a route through an upstream node if the upstream node is a fixed access node, and based upon a quality of the beacons received from the upstream fixed access node.

10. The method of claim 9, further comprising the fixed access nodes selecting the route based upon a reverse link quality between the fixed access node and the upstream access node.

11. The method of claim 1, wherein the mobile access node selects a mobile access node as an upstream access node if the mobile node does not receive beacons from an upstream fixed node having a quality above a threshold.

12. The method of claim 1, wherein mobile access nodes advertise an ESSID that is different from any ESSID that is advertised by any fixed access nodes.

13. The method of claim 1, further comprising the mobile access node switching off an Ethernet wired interface if a routing path to any one of available gateway access nodes having a quality greater than a threshold is not available to the mobile access node.

14. The method of claim 1, wherein if a routing path to the gateway access node having a quality greater than a threshold is not available to the mobile access node, the mobile access node ceases advertising of a configured set of ESSIDs and stops accepting associations on the configured ESSIDs.

15. The method of claim 9, wherein if one of the fixed access nodes cannot select a routing path to the gateway access node having a quality greater than a threshold, the fixed access node ceases advertising of a configured set of ESSIDs and stops accepting associations on the configured ESSIDs.

16. The method of claim 1, wherein if the mobile access node cannot select a routing path to the gateway access node having a quality greater than a threshold, the mobile access node starts advertising a “

standalone”

SSID to aid in recovery.

17. The method of claim 1, wherein fixed access nodes can be configured to operate as mobile access nodes.

18. The method of claim 1, wherein mobile access nodes can be configured to operate as fixed access nodes.

19. The method of claim 1, further comprising a client connected to a first access node roaming to a second access node, the first access being at least one of a fixed access node and a mobile access node, the second access node being at least one of a fixed access node and a mobile access node, wherein the second wireless access node allows the client to maintain a same default gateway IP address as the client roams from the first access node to the second access node.

20. The method of claim 19, further comprising the second access node detecting the client, wherein detecting the client comprises:

detecting a MAC address of the client;

determining an IP address of the client.

21. The method of claim 19, wherein detecting the client further comprises:

receiving an association request from the client.

22. The method of claim 19, wherein detecting the client further comprises:

determining client information parameters.

23. The method of claim 22, wherein determining client information parameters comprises at least one of determining an IP address of client'"'"'s default gateway, determining a length of a DHCP lease, determining a time the client was last on the network, determining an IP address of the client.

24. The method of allowing a client to access a wireless system of claim 1, wherein the first access node references at least one of:

a first gateway within a same cluster as the first access node, and another gateway, to obtain client information regarding the client.

25. The method of allowing a client to access a wireless system of claim 1, wherein the first access node obtains the client information from a gateway by sending an anti-ARP request.

26. The method of allowing a client to access a wireless system of claim 1, wherein if a first requested gateway does not have the client information, then the first requested gateway requests the client information from another gateway.

27. A method of an access node selecting a routing path through a mesh network that includes mobile access nodes, comprising:

the access node of the mesh network receiving routing beacons from at least one upstream access node, the routing beacons including information of upstream access nodes along a path to a gateway access node;

the access node selecting a route through an upstream access node based upon;

c) a quality of beacons received from at least one upstream access node, and

d) whether the at least one upstream access node is a fixed access node or a mobile access node.