The paper presents a theoretical and experimental study on continuous-variable quantum passive optical networks (CV-QPON) for secure quantum key distribution (QKD) in large-scale quantum networks. The authors propose a novel protocol that leverages the wave-like properties of coherent states and electric-field quadrature measurements to enable deterministic and simultaneous key generation among all network users. This approach overcomes the limitations of probabilistic or time-sharing strategies used in previous quantum access network implementations. The CV-QPON protocols are designed to work with standard telecom technologies and existing access network infrastructure, making them cost-effective and scalable. The security of the protocols is analyzed in two scenarios: an untrusted protocol where users assume others may be adversaries, and a trusted protocol where users collaborate against an eavesdropper (Eve). The trusted protocol addresses information leakage by establishing a hierarchical system of trust among users, ensuring that the final keys are independent and secure. Experimental demonstrations were conducted using a setup with eight users, each with an 11 km access link. The results show that the trusted protocol achieves a total network key rate of 2.1 Mbits/s, compared to 1.5 Mbits/s for the untrusted protocol, demonstrating a 30% improvement in key generation rate. The CV-QPON protocols offer a promising pathway for building low-cost, high-rate, and scalable quantum access networks, with potential applications in large-scale quantum communication infrastructure projects like EuroQCI.The paper presents a theoretical and experimental study on continuous-variable quantum passive optical networks (CV-QPON) for secure quantum key distribution (QKD) in large-scale quantum networks. The authors propose a novel protocol that leverages the wave-like properties of coherent states and electric-field quadrature measurements to enable deterministic and simultaneous key generation among all network users. This approach overcomes the limitations of probabilistic or time-sharing strategies used in previous quantum access network implementations. The CV-QPON protocols are designed to work with standard telecom technologies and existing access network infrastructure, making them cost-effective and scalable. The security of the protocols is analyzed in two scenarios: an untrusted protocol where users assume others may be adversaries, and a trusted protocol where users collaborate against an eavesdropper (Eve). The trusted protocol addresses information leakage by establishing a hierarchical system of trust among users, ensuring that the final keys are independent and secure. Experimental demonstrations were conducted using a setup with eight users, each with an 11 km access link. The results show that the trusted protocol achieves a total network key rate of 2.1 Mbits/s, compared to 1.5 Mbits/s for the untrusted protocol, demonstrating a 30% improvement in key generation rate. The CV-QPON protocols offer a promising pathway for building low-cost, high-rate, and scalable quantum access networks, with potential applications in large-scale quantum communication infrastructure projects like EuroQCI.