The Bioteknix C3-400 Plus Door Access Control System is based on advanced embedded control and network communication technology designed to manage and regulate entry across four independent access points. The system integrates hardware and software to authenticate users through multiple verification methods, including RFID cards, passwords, and QR codes. It operates on TCP/IP and RS-485 communication protocols, enabling real-time data exchange and centralized monitoring. Equipped with high-speed processors, encrypted data transmission (AES-256), and large memory capacity, it ensures reliability and security in multi-door environments. The system supports event recording, time zone management, anti-passback, and linkage control, making it suitable for complex security infrastructures such as corporate offices, educational institutions, and industrial facilities. The C3-400 Plus exemplifies modern access control theory by combining automation, identification, and networked security in one integrated platform.