This paper addresses the challenges of maintaining sensing coverage and connectivity in large wireless sensor networks by keeping a minimal number of sensor nodes active. The authors investigate the relationship between coverage and connectivity, proving that if the radio range is at least twice the sensing range, complete coverage implies connectivity. This allows the focus to be solely on the coverage problem. Under the ideal case of high node density, the paper derives optimality conditions for selecting a subset of working sensor nodes to achieve full coverage. Based on these conditions, a decentralized and localized density control algorithm, Optimal Geographical Density Control (OGDC), is proposed. OGDC aims to minimize the number of active nodes while ensuring complete coverage and connectivity. Simulation results using ns-2 show that OGDC outperforms existing algorithms in terms of the number of active nodes required and achieves similar or better coverage. The paper also discusses related work and provides a detailed overview of OGDC, including its implementation and parameter tuning guidelines.This paper addresses the challenges of maintaining sensing coverage and connectivity in large wireless sensor networks by keeping a minimal number of sensor nodes active. The authors investigate the relationship between coverage and connectivity, proving that if the radio range is at least twice the sensing range, complete coverage implies connectivity. This allows the focus to be solely on the coverage problem. Under the ideal case of high node density, the paper derives optimality conditions for selecting a subset of working sensor nodes to achieve full coverage. Based on these conditions, a decentralized and localized density control algorithm, Optimal Geographical Density Control (OGDC), is proposed. OGDC aims to minimize the number of active nodes while ensuring complete coverage and connectivity. Simulation results using ns-2 show that OGDC outperforms existing algorithms in terms of the number of active nodes required and achieves similar or better coverage. The paper also discusses related work and provides a detailed overview of OGDC, including its implementation and parameter tuning guidelines.