Among the various quantum key distribution (QKD) protocols, SARG04 was proposed as a modification of the wellknown BB84 protocol to enhance its resilience against sophisticated eavesdropping strategies, particularly the Photon Number Splitting (PNS) attack. Evaluating the performance and security of such protocols in realistic scenarios is crucial for their practical deployment. This paper introduces a comprehensive simulation framework developed in Python using the Qiskit library to analyze the SARG04 protocol. The simulator models realistic conditions by incorporating system noise and implementing two significant attack strategies: the PNS attack and the partial intercept-resend attack. We conduct an extensive experimental analysis of the protocol’s performance, primarily in terms of the Quantum Bit Error Rate (QBER), using various simulated quantum backends provided by IBM’s Qiskit. Furthermore, we assess the protocol’s security by quantifying the amount of information an eavesdropper can acquire. Based on the simulation data, we derive empirical formulas to predict the QBER and the information leakage under different attack parameters. These formulas are then validated against an independent backend, demonstrating their accuracy and predictive power. This work provides a practical demonstration of the feasibility and robustness of the SARG04 protocol and offers a valuable tool for future research in QKD.