High Assurance Smart Metering

This paper describes a high assurance architecture for smart metering. Hacking the smart metering infrastructure can have an enormous physical impact, therefore, it is essential that the components in this architecture are proven to be secure. In order for components to be verifiable, however, they need to be sufficiently simple. In this paper, we map the functionalities and different software modules of a smart meter to a minimal number of physical components in order to obtain a cost-effective and secure smart meter. The resulting smart meter contains seven physical components: a clock, a metrology component, a display, an off-switch, memory and two processors. It contains six main software modules: a communications module, a computations module, a credit balance module and three separate security modules, one of which is implemented on the second processor. Finally, there are six strongly separated memory segments: three for log files, one for the tariffs, one for the credit balance and one containing the operational parameters.