Secure communication is an increasingly important application of the Internet. Without secure communication many existing social functions cannot benefit from modern technology. The primary example is commerce. The foundation of secure communication is cryptography, which enables secure communication through the use of keys. The management of these keys has proven to be a problem when the technology is taken into use. So called public key cryptography solves several of these problems, in particular it allows the keys to be transfered, in the form of a certificate, through unprotected communication cannels
