In this paper a reliability based routing algorithm is proposed for wireless sensor
networks achieving reliable packet transfer to Base Station with minimum energy. The
link metric used for calculating the optimal path is related to the corresponding
fading model (e.g. Rayleigh, Rice or any arbitrary fading model). The proposed scheme
minimizes the energy consumption and ensures reliable packet transmission at the same
time. Reliability is guaranteed by selecting the path over which the probability of
correct packet reception at the base station will exceed a predefined threshold. While
energy balancing is ensured by selecting the path which minimizes the energy consumption
of the "bottleneck node" (i.e the energy consumption of the crucial node, having minimal
remaining energy in the routing path). It will be pointed out that reliable and energy
efficient packet forwarding can be put down to a constrained optimization problem.
By using a specific link metric, this problem can than be mapped into a shortest path
problem solved in polynomial time. Thus the obtained results make possible reliable
path selection with optimal energy balancing in real time.