1. A method in a network node for distributed network address allocation, comprising: maintaining an integer seed value n and an integer state value s, with a configuration parameter of the node being determined from the seed value n; receiving a request from a new node wishing to join the network and itself adapted to perform the method; generating a proposed seed value using the formula (n+2 s ) and a proposed state value using the formula (s+1); offering the proposed seed and state values to the new node; and, if the proposed seed and state values are accepted by the new node, updating the node's state value s to be the same as that accepted by the new node.