To address shortcomings in the prior art, the invention uses fate sharing information to compute backup paths. Fate sharing information relates groups of nodes or links according to common characteristics, attributes, or shared resources (e.g., a shared power supply, close proximity, same physical link). In one embodiment, fate-sharing information includes costs associated with groups of nodes or links. When a primary path contains a link or node that is in a fate-sharing group, the other links or nodes in the fate-sharing group are assigned the cost associated with that fate-sharing group. The node computing the backup path takes into account the assigned cost together with other node and link costs. Discovering the existence of the relationships and assigning costs to the groups may be done manually or automatically.