Design and evaluation of large-scale and real-time remote control architectures for home appliances

This paper presents the system architecture of bidirectional communication for remote control of home devices. For remote control systems, WebSocket is a promising technology since it is feasible for typical home users and enables low-latency communications of interactive operations. However, current WebSocket-based remote control systems do not take into consideration the problems concerning scalability and operational costs that exists in the case of large-scale environments. The proposed architecture, named Mediation architecture, features scalability and the hosting of connections from a home device and a user application at the same server to ensure low-latency communications. We also incorporate an automated scaling mechanism to reduce operational costs. It adaptively adjusts the number of WebSocket servers depending on their load states and automatically configures a newly launched server. The experimental results obtained in a testbed environment indicate that the proposed system provides low latency that is practical for an actual service and that works with moderate resource consumption. We also show that, as expected, the automated scaling mechanism detects the need to launch a new server or to isolate a down server and keeps the normal working state as a whole.