Regaining Insight and Control on SMGW-based Secure Communication in Smart Grids

Smart Grids require extensive communication to enable safe and stable energy supply in the age of decentralized and dynamic energy production and consumption. To protect the communication in this critical infrastructure, public authorities mandate smart meter gateways (SMGWs) to be in control of the communication security. To this end, the SMGW intercepts all inbound and outbound communication of its premise, e.g., a factory or smart home, and forwards it on secure channels that the SMGW established itself. However, using the SMGW as proxy, local devices can neither review the security of these remote connections established by the SMGW nor enforce higher security guarantees than established by the all in one configuration of the SMGW which does not allow for use case-specific security settings. We present mechanisms that enable local devices to regain this insight and control over the full connection, i.e., up to the final receiver, while retaining the SMGW's ability to ensure a suitable security level. Our evaluation shows modest computation and transmission overheads for this increased security in the critical smart grid infrastructure.