Network analysis method

A network made up of sub-networks with associated nodes is automatically assessed to determine whether any local server (N5) should be moved from its existing sub-network (X3) to a different sub-network, a local server being a server which principally communicates with one particular sub-network. This assessment involves notionally locating the local server (N5) concerned on each sub-network (X1-X4) in turn and evaluating for each such location of the local server (N5), a predetermined optimal-location function that provides a measure of the traffic between sub-networks that would be associated with local server (N5) in its current notional location. The assessment further involves identifying as the optimum sub-network for the local server (N5), that sub-network (X4) for which evaluation of the optimum-location function indicates a minimum for traffic between sub-networks.