مجلة الاربعين المحكمة
This paper presents the design of a new stream cipher cryptosystem (CS) with a new Key Generator (KG). Firstly, we presented the mathematical model of the new CS, which is based on Linear Feedback Shift Registers (LFSR) units with non-linear combined functions to increase the complexity of the design CS. This cryptosystem can be used to protect data transmitted (online or offline) during the Arbaeen pilgrimage commemorating Imam Hussein's martyrdom, peace be upon him, whether by pilgrims or/and military protection units affiliated with the army or police. To test the output key results, we apply Basic Efficiency Criteria (BEC) to the suggested KG. The results of using BEC demonstrate the robustness and efficiency of the new stream cipher CS