Hyperentanglement, as a high-dimensional quantum entanglement phenomenon across multiple degrees of freedom, plays a critical role in quantum communication, quantum computing, and high-dimensional quantum state manipulation. Unlike entangled states in a single degree of freedom, hyperentangled states establish entanglement relations simultaneously across multiple degrees of freedom, such as polarization, path, and orbital angular momentum. Through entanglement-based distribution techniques, high-dimensional quantum information networks can be constructed. Based on this, this paper establishes a hyperentangled fully connected quantum network, realizing polarization and time-bin degree-of-freedom hyperentanglement through the process of second-harmonic generation and spontaneous parametric down-conversion in periodically poled lithium niobate (PPLN) waveguide cascades. The hyperentangled state is then multiplexed into a single-mode fiber using dense wavelength division multiplexing (DWDM) technology for transmission to terminal users. The quality of the entangled states in the two degrees of freedom is characterized using Franson-type interference and photon-pair coincidence measurement techniques. Polarization entangled states are subjected to quantum state tomography, and entanglement distribution technology is employed to achieve long-distance distribution and quantum key transmission within the network. Experimental results show that the two-photon interference visibility of both polarization and time-bin entanglement is greater than 95%, demonstrating the high quality of the hyperentanglement in the network. After 100 km of entanglement distribution, the fidelity of the quantum states in both degrees of freedom remains above 88%, indicating the effectiveness of long-distance entanglement distribution in this network. Additionally, we verified that this network supports quantum key distribution over distances exceeding 50 km between users. These results confirm the feasibility of a hyperentangled fully connected quantum network and demonstrate the potential for constructing large-scale metropolitan networks using hyperentanglement. As a higher-dimensional entanglement, hyperentangled states can significantly enhance the capacity and efficiency of quantum information processing. While quantum communication is still in its early stages of development, achieving stable storage and transmission of entangled states in large-scale metropolitan networks remains a significant challenge. By utilizing the frequency conversion properties and high integration characteristics of the periodically poled lithium niobate waveguide, the three-user hyperentangled quantum network constructed in this work provides a new solution for the development of large-scale metropolitan networks for high-dimensional quantum information networks, and it is expected to offer a new platform for quantum tasks such as superdense coding and quantum teleportation
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