Method and apparatus providing registered mail features in an electronic communication system

摘要

The method and the apparatus provide a security feature in an electronic communication system which contains a first and a second terminal and a communication network. The first terminal is designed for sending a message to the second terminal. A security service station is provided to communicate with the first and second terminals via the communication network. In the first terminal a key is generated at random which is used for encrypting the message, thereby obtaining a first encrypted message. A first quantity of data defining this first encrypted message and the random key form a composed data quantity which is encrypted with a first secret key. This key is specifically assigned to the first terminal. A first encrypted composed quantity of data is obtained which is sent from the first terminal to the security service station. The first encrypted message is transmitted from the first terminal to the second terminal. Here, a second quantity of data defining the first encrypted message is derived. This quantity of data is encrypted with a second secret key which is specifically assigned to the second terminal. Thereby, a second encrypted quantity of data is obtained which is sent to the security service station.