We assume that the graph G, with a set of vertices V , edges
E, and edge failure probabilities P, is at least two-connected.
Since only single-link failures are considered, edge failures
are disjoint events, which gives
P
fi;jg2E pij = 1. Similar to
previous works , the primary flow is restricted to a single path.
After the failure of a link, a network management algorithm
reroutes the traffic along the allocated protection paths. Due
to space constraints, in this paper we do not consider backup
resource sharing. A full treatment of the MAGP problem
with resource sharing can be found in [19]. Without loss of
generality, for the remainder of this paper unit demands are
assumed.