Abstract: A system and method for supporting multicast in highly dynamic wireless multi-hop networks, such as ad-hoc networks, with good scalability. The system and method provide a multicast routing algorithm to work in wireless ad-hoc networks without any fixed infrastructure nodes present. In doing so, the system and method provide a technique to build a multicast source specific tree on demand, while using a core source node to limit routing overhead. The system and method further provide a repair process to reduce the latency of discovery of topology change, employ a node sequence number mechanism to differentiate between upstream nodes and downstream nodes on the multicast tree in the repair process, and provide an active joining process to reduce the latency of discovery of membership change.

Abstract: A system and method for a media access control (MAC) scheduling algorithm having a distributed, self-coordinating approach to provide use fairness and service differentiation in an ad hoc network by using control RTS/CTS messages carrying node status information. A local scheduling algorithm uses the overheard RTS/CTS information with attributes specifying nodes' status to maximize the awareness of the neighborhood status for a multi-channel system where data and ACK messages are transmitted through different data channels. If the system uses a single channel, the corresponding information may be carried by using DATA or ACK messages. The algorithm measures the offered load, carried load, and backlogged load in the neighborhood to adjust the channel access timer to provide use fairness among different nodes, different links, and different streams.

Abstract: A system and method to control congestion in a multihopping wireless communication network (100). The system and method distribute the congestion information back to the ingress points (106) and traffic source nodes (102, 106, 107) in the network (100) through the actual route of the data flow that contributes to the congestion. The system and method therefore avoid bottleneck points (102-5) in the network (100) to reduce congestion. The system and method can be used for packet-based, route-based or flow-based traffic shaping in a multihop wireless network (100) employing different media access control (MAC) and routing layer protocols. Moreover, the system and method is capable of distributing congestion and service differentiation information between different interfaces in the network (100).

Abstract: The proposed multicast architecture for multi-hop wireless mesh networks addresses a very important but never discussed and studied problem for wireless mesh networks to efficiently support multicast applications. The proposed multicast architecture for multi-hop wireless mesh networks enables the mesh networks to join the global multicast group seamlessly, and extend the multicast support to any routable or non-routable devices in the wireless mesh networks.

Abstract: A system and method for providing a polling scheme to improve medium access control (MAC) in a multihop wireless communication network (100) comprising nodes (102) and access points (106). When an access point (106) is the source of data packets being transmitted to a neighbor node (102), a collision-avoidance protocol is employed for the communication. However, when the access point (106) is to be the receiver of data packets transmitted from a neighbor node (102), the access point (106) polls the neighbor node (102) by initiating contact with the neighbor node (102) and inviting the neighbor node (102) to send queued data packets to the access point (106). As a result, the polling process allows the access point (106) to gain limited control over its neighbor nodes (102) and increase the efficiency of the network (100).

Abstract: A system and method for calculating a routing metric that can select the route providing the best throughput in a multihopping network (100), based on one or more parameters including completion rates, data rates, MAC overhead and congestion. The system and method are capable of selecting a route in a multihopping network (100) having a high throughput, comprising calculating a routing metric at one or more nodes (102, 106, 107), wherein the routing metric enables the one or more nodes (102, 106, 107) to select the route in the network (100). The routing metric can include network information such as the raw data rate, the completion rate, and the media access control overhead and congestion.

Abstract: A method and system for routing data in a wireless network (400) that enables all nodes (106, 402, 404, 406, 408) to find routes to each other even if the nodes (106, 402, 404, 406, 408) are non-meshed which are incapable of operating as a router to route packets received from other nodes (106, 402, 404, 406, 408), and for associating and reassociating the non-meshed and meshed nodes with other meshed nodes (106, 402, 404, 406, 408). The non-meshed nodes (STA 13-STA 15) request association with one of the meshed nodes (AP5) which are capable of performing packet routing, to request that the meshed node (AP5) with which the non-meshed node (STA 13) is associating operate as a proxy node to route packets between the associated non-meshed node (STA 13) and other meshed or non-meshed nodes (106, 402, 404, 406, 408).

Abstract: A method and system for routing data in a wireless network (400) that enables all nodes (106, 402, 404, 406, 408) to find routes to each other even if the nodes are incapable of operating as a router to route packets received from other nodes (106, 402, 404, 406, 408). The meshed nodes (106, 402) which are capable of performing packet routing act as proxy nodes for their associated non-meshed nodes (STA 13-STA 15) to route packets from their associated non-meshed nodes (STA 13-STA 15) to destination nodes. Some of the meshed nodes further operate as intelligent access points (106) to provide the non-meshed nodes and other meshed nodes with access to other networks, such as the Internet (402).

Abstract: Provided is a system and method for a multicast routing algorithm to work in infrastructure based mesh networks. It chooses access points, fixed infrastructure gateway nodes connected to each other and/or the global internet via a wired/wireless backbone, as a group of local multicast group leaders to form a multicast group leader cloud. Each local multicast group leader is elected on-demand according to the local multicast group member's request. Each local multicast group leader forms a local multicast tree rooted at this leader connecting all multicast group members associated with the AP. The processes of electing and maintaining local multicast trees rooted at APs enable efficient coordination with underlying unicast routing to exploit the advantages of fixed infrastructure nodes. Therefore, routing overhead and multicast tree convergence time are reduced. The method can support large networks with fast topology change due to fast convergence and reduced routing overhead.

Abstract: A system and method for providing a traffic control scheme for QoS provision and congestion control across multiple interfaces of wireless nodes (102, 106 and 107), such as wireless access points (107 and 106), communicating in a wireless multihopping communication network (100). The nodes (102, 106 and 107) can include multiple transceivers. The system and method detects bottleneck interfaces in these nodes (102, 106, 107) to control the traffic along the path of the corresponding traffic flow. Different measurements and cross-layer feedback are used to differentiate the cause of the congestion, such as wireless link quality degradation due to fading or degradation due to congestion in a shared medium. The nodes (102, 106, 107) inform each other on the status of their congestion level. High and low level signaling and interruption mechanisms are used to control the interfaces of the congested node (102, 106 or 107) to adjust traffic flow and alleviate the congestion.

Abstract: The present invention provides a system and method to detect transient links in a timely and reliable way. The present invention introduces a metric that depends on the unicast data timeout measurements at the receiver node (102, 106, 107). This metric can be combined with existing solutions to estimate the link quality between nodes (102, 106, 107). Furthermore, the present invention takes the packet size into consideration when transceivers (108) update the link quality based on the packet completion rate to quantify the transient link quality more precisely.

Abstract: A system and method for selecting a route from multiple potential routes in wireless network is shown. The present invention sends multiple route requests with the same route request identifier value concurrently to multiple candidate routes to obtain accurate bi-directional route metrics for candidate routes. The route having the best route metrics among the candidate routes is selected as the new route for communication through the wireless network.

Abstract: A system and method for improving the performance of an on-demand routing protocol in a wireless network is provided. The invention provides improved system performance of a wireless network by enabling nodes following an on-demand routing protocol to process (and possibly reply to) route request messages multiple times based on the routing metrics.

Abstract: A system and method for a media access control (MAC) scheduling algorithm having a distributed, self-coordinating approach to provide use fairness and service differentiation in an ad hoc network by using control RTS/CTS messages carrying node status information. A local scheduling algorithm uses the overheard RTS/CTS information with attributes specifying nodes' status to maximize the awareness of the neighborhood status for a multi-channel system where data and ACK messages are transmitted through different data channels. If the system uses a single channel, the corresponding information may be carried by using DATA or ACK messages. The algorithm measures the offered load, carried load, and backlogged load in the neighborhood to adjust the channel access timer to provide use fairness among different nodes, different links, and different streams.

Abstract: A system and method for data transmission using a multichannel medium access control (MAC) protocol to send small messages on the reservation channel directly without any RTS/CTS handshake or channel switching delays. The message is assigned a special type so that it can be distinguished from the RTS/CTS message. The message can also include information about congestion, activity, device type, mobility level, and so forth.