Secure network communication method

A secure-network-communication method comprising an endpoint and a relay gateway connected with a first network, and an application gateway connected to the relay gateway via a second network, said method comprising:

• initialization of each endpoint, whereby the application gateway generates first and second authenticators that are asymmetrical to each other based on an individual identifier that is unique to each endpoint and an authentication password, and the second authenticator is stored in a whitelist for management and the first authenticator is stored in the endpoint;
• authentication at the initialization of the endpoint, whereby the relay gateway receives, from the endpoint, data that includes an individual identifier and an operation value obtained from the encrypted first authenticator, and determines the validity of the first authenticator;
• if the relay gateway determines that the first authenticator is valid, it generates new asymmetric first and second authenticators using randomly generated numbers, and then transmits the authenticators to the application gateway, so that the application gateway updates the second authenticator in the whitelist and adds a record to a timeline log, and the endpoint updates and stores the first authenticator;
• and
• arrangement of common keys, whereby the relay gateway receives a first number randomly generated by the endpoint and a third number randomly generated by the application gateway;
• the relay gateway generates part of an encryption key using a second number randomly generated by the relay gateway and the first random number, and transmits that part of the encryption key to the application gateway;
• the relay gateway generates another part of an encryption key using the second random number and the third random number, and transmits said another part of the encryption key to the endpoint;
• the application gateway generates an encryption key by using said another part of the encryption key and the third random number, and stores the generated encryption key in the whitelist;
• and the endpoint generates an encryption key by using the other part of the encryption key and the first random number, and then stores the generated encryption key.