The Pocket Companion's architecture.

The Pocket Companion is a small personal portable computer with wireless communication facilities. The typical use of the Pocket Companion induces a number of requirements concerning security, performance, energy consumption, communication and size. The energy consumption due to the increasing demand for performance and functionality will be the limiting factor for its capabilities. Therefore reducing energy consumption plays a crucial role in the architecture. Communication, and particularly wireless communication, is essential for the system to support electronic transactions. Such a system requires a good security infrastructure not only for safeguarding personal data, but also to allow safe transactions.