Flexible Updates of Embedded Systems Using Containers

Abstract: In this thesis the operating-system-level virtualization solution Docker is investigated in the context of updating an embedded system on application level. An updating sequence is designed, modelled and implemented, on which experiments are conducted to measure uptime and current. Within the popular notion of the Internet of Things, more and more things are being connected to the Internet and there by the possibility of dynamic updates over the Internet is created. Being able to update remotely can be very benecial, as systems may be costly or unpractical to reach physically for software updates. Operating-system-level virtualization, software containers, are a lightweight virtualization solution that can be used for dynamic updating purposes. Virtualization properties, like resource isolation and letting software share hardware capabilities are used in determining the architecture. The container architecture used is a microservice architecture, where systems are composed from many smaller, loosely coupled services. The application area for the results of this thesis are start-ups in the Internet of Things eld, delimited to low complexity systems such as consumer products. The update regime is created with the properties of microservice architectures in mind, creating a self-propelling, self-testing, scalable and seamless dynamic updating process that can be used for systems of dierent complexity. The update regime is modeled to give proof of concept and to help design the implementation. The implemented update regime was made on an ARM based single board computer with a Linux-kernel based operating system running Docker. Experiments were then conducted in order to give a clear indication of the behavior of a dynamically updated embedded system. The experiments showed that the update regime can be seamless, meaning that the uptime properties are not aected by this kind of updating. The experiments also showed that no signicant changes in current can be noted for container limitations during this kind of update.