A process is disclosed for routing service requests through a network comprising nodes interconnected with links. The network is also arranged so that each node may communicate with each of the other nodes. At preselected time intervals, sets of routes through the network are generated in response to the network configuration and traffic information. Also, at predetermined time intervals, occupancy factors are computed as determined by the network configuration and in response to traffic information. These occupancy factors are proportional to unassociated occupancy factrors and allocation factors associated with calls of the various node-pairs; each of these latter factors is derived from a nominal routing scheme in which a call of the corresponding node-pair is treated as lost only if it is blocked on all of its permitted routes. At predetermined intervals, traffic usage data is measured. At regular intervals, the occupancy factors corresponding to the busy-idle status of the links are used to compute occupancy values associated with each of the routes. Occupancy values not exceeding a threshold generate sequential route sets for each interval. Offered traffic is sequentially routed over the sequential route sets.