A wireless communications network generally comprises a plurality of wireless communications nodes that are distributed geographically within a region. The nodes communicate with one another through wireless links between the nodes. Control in a wireless communications network can be either centralized or distributed through the network. In a centralized network, control is maintained within one or more centralized base station nodes in the network. Each of the base station nodes is within range of some or all of the wireless nodes in the network. All communications between nodes in the centralized network take place through at least one of the base station nodes. The base station nodes also determine how the message will be routed from a source node to a destination node.
In a distributed network, there is no centralized control in the network. That is, connections between nodes in the network are set up by the individual nodes without the intervention of a base station. If two nodes are not within communications range of one another, a connection is established between the nodes using a series of node-to-node links. Routing decisions are made within the individual nodes. Networks following this approach are sometimes referred to as "ad-hoc" networks. In general, ad-hoc networks are not constrained to using predefined links to provide a connection between two nodes. Instead, such networks can establish a connection between nodes by using any combination of available node-to-node links to connect the desired nodes.
As can be appreciated, a connection between two nodes in a wireless communications network, whether centralized or distributed, is only as sound as the individual links that make up the connection. That is, if one of the links that is used to establish the connection is of poor quality, the overall connection will be of poor quality. For example, if one of the links is only capable of supporting a relatively low data rate, the entire connection is constrained by this data rate. In addition, if one of the links fails during a communication, the entire connection fails.
Therefore, there is a need for a method and apparatus that is capable of enhancing connectivity in a wireless communications network by intelligently selecting the wireless links that are used to establish connections between nodes in the network.