Towards an understanding of the tradeoffs in adversary models of smart grid privacy protocols

Maintaining privacy while still providing the advanced functionality of the smart grid is a very important topic in the power and energy communities. Recently proposed protocols attempt to solve the associated problems in such a way that privacy is maintained. These protocols are typically proven secure under one of two adversary models: the honest-but-curious model or the malicious model. The honest-but-curious model is the weaker of the two in that adversaries are assumed to be honest in carrying out the protocol without deviation but use any information gathered during the process to violate another party's privacy. This model is often justified in the literature by assuming that devices are tamper resistant. It turns out that each of these models has its benefits and disadvantages. Add in the assumption of anti-tamper protections, and the story becomes even more complicated. In this work, we initiate a look at the tradeoffs of the two models (along with the anti-tamper assumption) by comparing one privacy preserving data-aggregation protocol from each model found in the published literature. We examine the computation and communication complexities of each protocol and study how these affect the scalability of the protocols. We also comment on anti-tamper protections and their associated computational costs.