Method for Maintaining Links in a Mobile Ad Hoc Network

A method of maintaining data links to and from a source node in an ad hoc mobile network,

• wherein the network comprises nodes including neighbour nodes corresponding to nodes within range for direct communication with the source node, the neighbour nodes comprising active neighbour nodes and inactive neighbour nodes, the active neighbour nodes being connected to the source node via respective active data links and the inactive neighbour nodes having respective inactive data links to the source node, the active and inactive data links forming an existing configuration of data links,
• the method comprising:
• (1) identifying one or more lost neighbour nodes corresponding to neighbour nodes of the existing configuration that have moved out of range for direct communication with the source node and/or are about to move out of range for direct communication;
• (2) determining revised configurations of data links in which any active links to lost neighbour nodes are considered inactive and, for at least one revised configuration, an inactive link is considered active and/or a further active link is considered inactive;
• (3) determining an overall configuration value for each revised configuration based at least partly on the cost of sending messages from the source node using the revised configuration of data links;
• (4) selecting a new configuration of data links from the revised configurations according to the overall configuration values determined;
• and
• (5) forming the new configuration of data links by breaking data links with neighbour nodes that are active on the existing configuration list but inactive on the new configuration list, and forming data links with any neighbour nodes that are inactive on the existing configuration list and active on the new configuration list.