to implement segment 3 as part of the high priority restoral route and will then update rtt database 118 to indicate that segment 3 is part of the high priority restoral route and the unavailable segment 1 is part of the low priority restoral route as a result of this segment swap segment 3 which can be successfully and automatically implemented is now a part of the high priority restoral route therefore the high priority restoral route can be quickly implemented rather than depending on a repair to segment 1 segment 1 is now a part of the low priority restoral route but does not add to the time needed to implement this route this is became the time needed to repair segment 1 will be much less than the time needed to execute the manual actions that are required to implement a low priority route ______________________________________ not part of not used or priority priority priority restoral unavailable group 1 group 2 group 3 pre plan segments______________________________________restoralpre planset upsegment 1 s sub 1segment 2 s sub 2segment 3 s sub 3segmentsubstitutionsegment 1 s sub 1 u2192 s sub 1segment 2 s sub 2 u2190 s sub 2segment swapsegment 1 s sub 1 u2192 s sub 1segment 3 s sub 3 u2190 s sub 3______________________________________ fig2 5 are block diagrams of a network of dne nodes these figures illustrate the different scenarios in which the present invention operates fig2 illustrates.