1. Computer network configuration apparatus for use in a network including a plurality of network nodes interconnected by one or more network segments and a plurality of computers communicably coupled to selected ones of the plurality of network nodes, wherein the plurality of computers are operative to execute application programs thereon, the computer network configuration apparatus comprising: a plurality of local controllers, each of the local controllers associated with a corresponding network node having an associated memory containing a same plurality of end-to-end forwarding topologies identifying one or more network segments for forwarding traffic through the network; and wherein each local controller is configured to, independently of all other local controllers: deterministically select and utilize at least one of the plurality of end-to-end forwarding topologies as an initial forwarding topology and to maintain a non-selected one of the plurality of end-to-end forwarding topologies as an alternative forwarding topology, and in response to a change in a current network state, deselect the initial forwarding topology and independently and deterministically select and utilize the alternative forwarding topology in place of the initial forwarding topology, wherein each local controller is configured to select the same end-to-end forwarding topology as the initial forwarding topology and to select the same alternative end-to-end forwarding topology in response to the change in the current network state.