-\textbf{KEY WORDS:} Wireless Sensor Networks, Area Coverage, Network Lifetime, Optimization, Scheduling, Distributed Algorithms, Energy-efficiency.
+\textbf{KEY WORDS:} Wireless Networks, Wireless Sensor Networks, Area Coverage, Network Lifetime, Optimization, Scheduling, Distributed Algorithms, Centralized Algorithms, Robustness, Connectivity, Parallel Algorithms, Energy-efficiency, Heterogeneous Energy Network, Homogeneous Network.