Having valued possessions protected by an alarm system can significantly improve one's feeling of safety. Choosing a wireless alarm system (over a regular wired one) allows the end user to easily install it without construction, often making it a more attractive option. But opting into easy setup does not have to mean opting out of high reliability and security. Furthermore, wireless implementations feature great power efficiency, compensating for their lack of constant power supply.
We have designed and implemented protocol for wireless alarm system using LoRa technology. LoRa technology provides us with a long range of communication and minimal power consumption. The protocol we proposed is designed based on LoRa characteristics, ISM frequency band regulations and high demand for reliability and security. We incorporated all security mechanisms like checking integrity, authentication, encryption of the payload and prevention of replay attack. We have also defined handling of outage and system disruption.
Following the complete definition of the proposed protocol, we have implemented it using custom-built communication modules. We have added an administration board, server and a siren to make our alarm system complete.
We have tested the proposed solution, first by components and then as a whole.
Lastly, we evaluated the security of our system by comparing it to known ways of attack and determined that our solution is robust against common attacks. We have also calculated the highest possible and lowest possible battery life time for a battery with 1500 mAh capacity. Expected lifetime of that battery is 1.7 years when using the most optimal communication parameters, or 0.2 years when using the least optimal ones. Comparing our solution with a similar protocol, called ZigBee, showed that our solution fits better for alarm system application.
|
