METHOD TO OPERATE A WIRELESS NETWORK HAVING A PREDICTABLE AND STABLE PERFORMANCE

• US 20090245262A1
• Filed: 03/25/2008
• Published: 10/01/2009
• Est. Priority Date: 03/25/2008
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Yi, Yunjung, Ariyur, Kartik B., Varadarajan, Srivatsan
• Granted Patent: US 8,107,387 B2
• Time in Patent Office: Days
• US Class Current: 370/400
• 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
• CPC Class Codes: H04L 45/125 based on throughput or bandwidth
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/32 Flooding denial of service attacks H04L63/1458
• CPC Class Codes: H04W 40/12 based on transmission quality or channel quality
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for operating a wireless network having a predicable and stable network performance. The method includes controlling output distribution of nodes in the network to adapt to traffic changes in the network, distributing power control to adapt to environmental changes in the network, and providing traffic sensitive routing to adapt to topology changes in the network. The method also includes converging to set points based on the controlling of output distribution, the distributing of power control, and the providing of traffic sensitive routing.

Claims

1. A method for operating a wireless network having a predicable and stable network performance, the method comprising:

controlling output distribution of nodes in the network to adapt to traffic changes in the network;

distributing power control to adapt to environmental changes in the network;

providing traffic sensitive routing to adapt to topology changes in the network; and

converging to set points based on the controlling output distribution, the distributing of power control and the providing of traffic sensitive routing.

2. The method of claim 1, wherein controlling output distribution of nodes comprises:

determining a mean throughput at each node for an application;

determining a throughput variance at each node based on a quality of service required by the application;

analytically computing an end-to-end transport capacity, latencies, and loss probabilities based on the determinations of the mean throughput and the throughput variance at each node; and

implementing a gatekeeper between a network queue and a media access control queue to control input to each node based on the computations, wherein the mean throughput at each node and the throughput variance at each node are driven to a selected mean throughput and a selected throughput variance.

3. The method of claim 1, wherein distributing power control comprises:

setting setpoints of signal-interference-to-noise ratio by an outer-loop power controller to avoid saturation in the nodes;

controlling an inner-loop power to maintain desired link capacity; and

controlling an outer-loop power to prevent saturation.

4. The method of claim 3, wherein the setpoints of signal-interference-to-noise ratio at each node are proportional to the rate of information generation at the respective node.

5. The method of claim 1, further comprising:

implementing state information in each node to manage mobility by controlled flooding.

6. The method of claim 5, wherein implementing the state information in each node to manage mobility by controlled flooding comprises:

periodically exchanging information indicative of counter values with neighboring nodes;

receiving a packet at a node;

discarding the packet if a sequence number of the packet received at the node is a sequence number in an identifier-counter;

inserting an identifier into the identifier-counter if the sequence number of the packet received at the node is not a sequence number in the identifier-counter;

incrementing a received-packet-counter for a destination node responsive to inserting the identifier into the identifier-counter;

sending the packet to an application layer of the node if the node is the destination node;

inserting the packet into a holding queue if the node is not the destination node; and

sending the packet to at least one neighboring node responsive to inserting the packet into the holding queue.

7. The method of claim 1, wherein providing traffic sensitive routing comprises:

managing mobility by robust group forwarding when mobility dynamics are determined to be low; and

managing mobility by controlled flooding when mobility dynamics are determined to be high, wherein managing mobility is used to adapt to topology changes in the network.

8. The method of claim 7, wherein managing mobility by robust group forwarding comprises:

establishing a multi-path routing structure by,

finding multiple paths close to each other;

forming a multicast group from the multiple paths;

building a mesh forwarding structure based on the forming of the multicast group; and

forwarding packets received at each node in the multicast group.

9. The method of claim 7, wherein managing mobility by controlled flooding comprises:

simultaneously discovering multiple paths through the network and sending packets on the multiple paths; and

limiting exchange of information with neighboring nodes to maintain the information exchange at a low level.

10. The method of claim 7, wherein managing mobility by controlled flooding comprises:

providing an identifier to each node at a physical layer;

providing a selected number of destinations within the network at the physical layer;

maintaining an identifier-counter operable to track sequence numbers of packets received at the node at the physical layer;

maintaining a received-packet-counter operable to track a total number of packets received at the node for each of the destinations at the physical layer; and

maintaining a transmitted-packet-counter operable to track a total number of packets transmitted from the node for each of the destinations at the physical layer.

11. A wireless network comprising:

a plurality of nodes;

an output distribution control protocol at a network layer of each node for adapting to traffic changes in the network;

a distributed power control protocol at a media access control layer and a physical layer of each node for adapting to environmental changes in the network; and

a traffic sensitive routing protocol at the network layer of each node for adapting to topology changes in the network;

wherein the output distribution control protocol, the distribution power control protocol, and the routing protocol together function to stabilize nodes in the network to a predictable network performance during network disturbances.

12. The wireless network of claim 11, wherein network disturbances include one or more of changes in levels of traffic, changes in traffic sources, changes in mobility, changes in interference levels between nodes, changes in channel gains, and changes in link capacities.

13. The wireless network of claim 11, wherein the output distribution control protocol is operable to determine a mean throughput at each node for an application and to determine a throughput variance at each node based on the quality of service required by the application.

14. The wireless network of claim 11, wherein the distributed power control protocol is operable to set setpoints of signal-interference-to-noise ratio by an outer-loop power controller at the media access control layer, to control an inner-loop power at the physical layer, and to control an outer-loop power to prevent saturation.

15. The wireless network of claim 11, wherein the traffic sensitive routing protocol is operable to manage mobility by robust group forwarding when mobility dynamics are determined to be low at the network layer, and to manage mobility by controlled flooding when mobility dynamics are determined to be high at the network layer

16. A computer readable medium having instructions stored thereon for implementing a method for operating a wireless network having a predicable and stable network performance, the instructions comprising:

computer readable code for controlling output distribution of nodes in the network to adapt to traffic changes in the network;

computer readable code for distributing power control to adapt to environmental changes in the network;

computer readable code for providing traffic sensitive routing to adapt to topology changes in the network; and

computer readable code for converging to set points based on the controlling output distribution, the distributing of power control and the providing of traffic sensitive routing.

17. The computer readable medium of claim 16, wherein the computer readable code for controlling output distribution of nodes in the network comprises:

computer readable code for determining a mean throughput at each node for an application;

computer readable code for determining a throughput variance at each node based on the quality of service required by the application;

computer readable code for analytically computing an end-to-end transport capacity, latencies, and loss probabilities based on the determinations of the mean throughput and the throughput variance at each node; and

computer readable code for implementing a gatekeeper between a network queue and a media access control queue to control input to each node based on the computations, wherein the mean throughput at each node and the throughput variance at each node are driven to a selected mean throughput and a selected throughput variance.

18. The computer readable medium of claim 16, wherein the computer readable code for distributing power control comprises:

computer readable code for setting setpoints of signal-interference-to-noise ratio by an outer-loop power controller to avoid saturation in the nodes;

computer readable code for controlling an inner-loop power to maintain desired link capacity; and

computer readable code for controlling an outer-loop power to prevent saturation.

19. The computer readable medium of claim 16, wherein the computer readable code for providing traffic sensitive routing comprises:

computer readable code for managing mobility by robust group forwarding when mobility dynamics are determined to be low; and

computer readable code for managing mobility by controlled flooding when mobility dynamics are determined to be high, wherein managing mobility is used to adapt to topology changes in the network.