Hybrid cryptosystems
SSL/TLS protocols

The main idea behind the invention of hybrid cryptosystems is to enable dispersed users to build networks of trust around the Internet as freely and dynamically as possible. To achieve this, it is necessary to free oneself from a rigid, centralized external authority, which would at all times possess knowledge of all secrets and would limit the performance of the entire system to the limits of its own capabilities. Historically, cryptological networks, which are almost exclusively state-run, have always operated on the centralized principle of symmetrical key management. Apart from the fact that there was no alternative, this was perfectly in line with their doctrines, so there was no need to invent another system. (To a very large extent, this is still true today.) However,...