Reliable Wireless Sensor Networks in Smart Homes
Examensarbete för masterexamen
Computer systems and networks (MPCSN), MSc
Wireless sensor communications play a key role in the emerging Internet of Things digital ecosystem. As the industry now gets ready to roll out the second generation of IoT-devices, effort is directed to fully standardize the protocol suite of wireless sensor networks, and assure full IP connectivity with devices. The protocols CoAP andMQTT are possible candidates for a highly functional application layer for the Internet of Things in terms of reliable transmissions and adherence to the less verbose attributes of wireless sensor networks where sleep cycles are utilized in an effort to keep the overall power utilization of end nodes low. Given these attributes, the protocols limit the number of messages sent to the minimum necessity in order to convey a current sensor value or actuating data. In neglecting other forms of communications, such as keepalive correspondence, the element of uncertainty to whether devices are operational or not increases over time given the less verbose approach. This thesis aims to examine the need of basic communication between devices and server in Smart Home settings, in an eort to keep a updated state view of the network, and reduce this element of uncertainty while still trying to comply with the less verbose nature of constrained network environments. With a more immediate and up-to-date view of the network, the server is able to take action at a faster rate when devices in the network fail or are unable to communicate. This will make wireless sensor networks more applicable for soft real time systems where critical devices are used, such as wireless security systems. The thesis aims at providing an application level keep-alive algorithm, which can be independently operable, to serve as a viable option to keep a more up-to-date view of safety-critical devices in wireless sensor networks than offered by current protocols that are implemented in present-day operating systems for the Internet of Things such as RIOT OS and Contiki OS.
Data- och informationsvetenskap , Computer and Information Science