Secure Socket Layer (SSL) is a protocol that was developed to enable secure data transmission over the internet. SSL certificates are used, for example, for online banking or online shop solutions. All browsers such as Internet Explorer, Netscape, Mozilla Firefox, Safari etc. support this standard.

SSL offers encrypted connections between server and client with certificates according to the X.509 standard and thus enables the assurance of message integrity. For this purpose, SSL uses the public key procedure, whereby data is encoded with a publicly accessible key and can then only be decoded again with a private key. If a visitor now navigates with his browser to a protected website, the web server reports with the public key and establishes a secure connection to the client via an encrypted random number and the calculated key. This key is then used to exchange data between the server and the client.