Closing the Blinds: Four Strategies for Protecting Smart Home Privacy from Network Observers

The growing market for smart home IoT devices promises new conveniences for consumers while presenting novel challenges for preserving privacy within the home. Specifically, Internet service providers or neighborhood WiFi eavesdroppers can measure Internet traffic rates from smart home devices and infer consumers' private in-home behaviors. Here we propose four strategies that device manufacturers and third parties can take to protect consumers from side-channel traffic rate privacy threats: 1) blocking traffic, 2) concealing DNS, 3) tunneling traffic, and 4) shaping and injecting traffic. We hope that these strategies, and the implementation nuances we discuss, will provide a foundation for the future development of privacy-sensitive smart homes.