Decentralized Computing for Reliable Home Automation

Smart homes are distributed systems that should provide reliable home automation services. Distributed controllers have been used to improve the reliability of smart homes. However, despite the redundancy in controllers, the reliability of smart homes is hindered by the unreliable network infrastructure comprising home Wi-Fi and low-power wireless networks. As a result, smart homes cannot be trusted with much more than casual automation to date. This dissertation identifies the limitations of traditional fault-tolerant approaches that require inter-controller coordination over an unreliable network infrastructure. A new class of decentralized control paradigm named Banyan, with fully autonomous controllers, is introduced by this dissertation. The dissertation also presents a new coordination-less universal idempotent scheme that prevents duplicate actuation. Under a realistic system model for smart homes, it is proved that reliable, consistent, timely control decisions are made in a decentralized unison. This paradigm’s first test bed implementation is presented in the smart home context. Multiple controllers may contribute to running automation scripts at opportune points during their run and control flows among the controllers to enhance reliability and availability while maintaining consistency. This dissertation concludes with simulation and empirical results that demonstrate the capability of Banyan to support reliable automation in the presence of unreliable networks in the smart home.