Abstract: We present a system-level approach to quantum networking that integrates entanglement distribution, precision metrology, and quantum memory in deployed fiber environments. Polarization-entangled photons are distributed over stabilized links with active feedback control, achieving high visibility and robust channel uptime. Network-compatible calibration techniques, including synchronized power measurements and remote detector calibration, enable accurate and scalable system characterization. Ancilla-assisted process tomography (AAPT) is employed to characterize quantum processes and quantify channel performance with high fidelity, supporting stable multi-node operation. In parallel, electromagnetically induced transparency (EIT)–based quantum memory in cesium vapor cells is studied, with anti-relaxation coatings significantly improving storage efficiency and coherence time. Together, these results demonstrate a practical and scalable framework for real-world quantum networks.