Abstract: A system and method for performing topology control in a wireless network (100). The system and method operate to enable a node (102-1) to determine the link cost of a link between itself and another node (102-2), based on the number of nodes (102, 106, 107) that would be affected by message transmission by the node (102) and the other node (102-2), and the number of nodes (102, 106, 107) that would be affected by message reception by the node (102-1) and the other node (102-2). The number of nodes (102, 106, 107) affected by the message transmission and message reception at the node (102-1) and the other node (102-2) is affected by the transmit power of the control messages sent by the node (102-1) and the other node (102-2). The node (102-1) further bases routing decisions on the calculated link costs.

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: 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: A system and method that creates an abstraction of the physical layer of a wireless communication network (100), in particular, a wireless ad-hoc peer-to-peer communication network (100), and that normalizes the feedback from the physical layer to enable multiple types of nodes (102, 106, 107) in the wireless network to operate using a common wireless routing protocol. This routing protocol uses a link quality metric to determine the best route regardless of how it actually chooses the route or disseminates such link quality information. The generalized routing metric can be derived for any node (102, 106, 107), regardless of its relative performance or its media access control (MAC) technology. The system and method also create a transaction summary that can be used for link adaptation and link quality estimation to determine, for example, future data rates, link quality/routing metrics, and transmit powers.

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 system and method to avoid and control the bottleneck points in multi-hop wireless ad-hoc networks is described. This is achieved by using the overheard RTS/(N)CTS information to compute a weighted combination of the node's and neighbors weighted queue size. Rate limiting factor can be distributed by using ACK messages in case RTS/CTS is not enabled while node weight values can be distributed in DATA messages. Furthermore, rate limiting is based on two metrics that eliminate the problems of drop-tail schemes. Priority levels may be used for selective rejection to provide availability for emergency and system packets.

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.