Internet of things and implementation of local wireless sensor network

Abstract: This master’s thesis covers the research and development of a local wireless sensor network with capabilities for IoT (internet of things) applications and with the ability to monitor and automatically control a watering system with soil humidity as input. The goal with this thesis was to develop a system where the wireless communication within the local network is suited for low power and lossy networks (LLN). The system was to be controlled and monitored from a user interface which is available from the internet. A system was developed with a wireless network with a suited underlying network stack with protocols that was fitted for the constrained environment. The nodes send values to a website with a UI (user interface) where values can be monitored and the user can control the system and send values to specific nodes within the system. The sensor nodes communicate with protocols developed for low power networks and an edge router was built for the purpose of routing this network to the internet. Research in the internet protocol suite has come a long way and a large variety of protocols has been developed to fit almost every set of nodes with different battery lifetime, processing power, and memory size. This thesis shows that the communication stack can be modelled with suited protocols to be satisfactory for different internet of things applications with high energy efficiency.