  We develop an energy-efficient routing protocol in order to enhance the
stability period of wireless sensor networks. This protocol is called weighted
election protocol (WEP). It introduces a scheme to combine clustering strategy
with chain routing algorithm for satisfy both energy and stable period
constrains under heterogeneous environment in WSNs. Simulation results show
that new one performs better than LEACH, SEP and HEARP in terms of stability
period and network lifetime. It is also found that longer stability period
strongly depend on higher values of extra energy during its heterogeneous
settings.
