Abstract: A method of selecting one of a plurality of candidate devices (1-6) forming at least part of a wireless personal area network (WPAN) to be a controller of the WPAN. For each candidate device (1-6), distances between that candidate device and other devices of the WPAN are assessed. A centrally located one (3) of the candidate devices is selected to be the controller, taking said distances into account. The residual battery energy of the candidate devices may also be taken into account.

Abstract: A method of assessing a communication route comprising a plurality of links between nodes in a mobile ad-hoc network comprises calculating the two-hop residual bandwidth of each node I of the route as B I ? ( t ) = B - ? J ? N ? ( I ) ? B ? ( J ) ? where B is the raw channel bandwidth, the summation is the overall consumed bandwidth from node I's two-hop neighborhood nodes, J?N(I) and ? is a factor to account for protocol overhead, which may include handshaking, packet collision, re-transmission and/or back-off scheme traffic. An estimated transmission time for each of a plurality of links between said nodes may be calculated taking said two-hop residual bandwidth into account. For each possible route, a route efficiency function is determined at least by summing the estimated transmission times for all the links in the route, and the route in which the value of the route efficiency function is smallest is selected.

Abstract: In a mobile ad hoc network, a method of routing data and a mobile unit for use according to the method are arranged to find the relay capacity of a node and the lifetime of the node, and thereby determine whether the node can relay the data. The method and unit can find the relay efficiency of nodes and this information is used to route data traffic efficiently through a number of nodes along a route.