Along with the evolution and deployment of open systems, users become aware of the inherent risks of such systems and demand for an appropriate level of security.
Correct billing is one example for such a common requirement.
Non repudiation service for e-mail is an example for such a security service. A security architecture is not solely defined by the set of security features it offers. This section describes the security architecture of the PSCS system and its integration into the PSCS demonstrator system.