Edge-disjoint paths
= Edge-disjoint paths
Paths are edge-disjoint when no graph edge occurs in two of them. They may share internal vertices. If $r$ edge-disjoint client-to-server paths exist, fewer than $r$ failed links cannot destroy them all. For simultaneous link and node failures one instead needs <internally vertex-disjoint paths>, since one shared internal node could destroy several edge-disjoint paths at once.