A method of provisioning mesh communication networks is disclosed. The method involves simulating the performance of a proposed network design to ensure the proposed network design meets service level criteria before provisioning a network in accordance with the proposed network design. Such simulations are required to be comprehensive because highly improbable events can be sufficient to result in a mesh network not meeting the stringent performance criteria which such networks are required to meet. Known methods of provisioning rely on exhaustively listing the mesh network states which would adversely impact the service offered by a proposed network design as part of simulating the performance of the proposed network design—this is an error prone exercise since relevant network states can be missed. A simulation technique is proposed in which the network state after each event is represented by a weighted graph indicating a measure of path cost for each of the links in the mesh network. A graph searching algorithm is applied to seek a path across the graph, thereby systematically exploring paths over mesh network which could provide a suitable route for the service in the simulated network state represented in the graph. Networks are thus provisioned which meet stringent performance criteria without being over-engineered.