System and a method for secure data transfer using air gapping hardware protocol

A system for secure data transfer using air gapping, the system comprising:

• a first module comprising first module components;
• a second module comprising second module components;
• a bridge module comprising bridge module components;
• wherein the first module components comprise:
• a first module communication interface configured to communicate with a public network;
• a first module controller and a first module data interface configured to send and/or receive data from the public network;
• wherein the second module components comprise:
• a first read-only memory storing an operating system;
• a second read-only memory storing sets of private keys of the second module and at least one public key of another remote entity;
• a cryptographic unit configured to encrypt and/or decrypt data using the keys stored in the second read-only memory;
• a second module communication interface configured to communicate with a secured machine or a secured network to transmit data from and to the second module;
• a microcontroller and a second module data interface for communicating with the bridge module;
• wherein the bridge module components comprise:
• a bridge module controller;
• a bridge module data interface for communicating with the bridge module controller;
• a memory for storing data;
• a switch configured to selectively connect the bridge module data interface to either the first module data interface or to the second module data interface such that the first module data interface is never connected with the second module data interface;
• wherein the bridge module controller is configured to receive data from the second module, store the data in the memory, and send the data to the first module and/or to receive data from the first module, store the data in the memory, and send the data to the second module.