swIDch OTAC (One-Time Authentication Code) is an authentication technology designed for military Identification Friend or Foe (IFF) systems. The product generates dynamic, random authentication codes without requiring network connectivity, enabling military forces to identify friendly aircraft, vehicles, and personnel in battlefield environments. OTAC operates through unidirectional authentication, where the client device generates codes without communicating with a server. Each code is unique, time-limited, and changes with every authentication attempt to prevent cloning, spoofing, and signal hijacking attacks. The technology functions in off-the-network environments, addressing scenarios where internet connectivity is unavailable or unreliable. The system provides single-step identification and authentication using the generated code alone. An optional biometric component enables single-step multi-factor authentication. The technology eliminates the use of static credentials such as usernames and passwords, replacing them with constantly changing dynamic codes. OTAC includes configurable code parameters and a lightweight SDK/applet for deployment across various devices and sectors. The technology has been tested and validated by the University of Surrey. Use cases include drone identification systems and military command and control applications where preventing fratricide and accurately identifying targets is critical.