Abstract:
The Internet of Things (IoT) concept has attracted significant attention from both industrial and research
communities. Nevertheless, the IoT is facing many security issues such as authentication, availability, privacy, and trust
management. Indeed, establishing trust relationships between nodes in IoT represents a primary security milestone to have
a reliable system that excludes malicious nodes. However, trust management in an IoT constrained, and ubiquitous
environment represents a challenge. In this thesis, we study the issue of designing secure trust management protocols taking
into account the specificities of IoT. In the IoT Low-Power and Lossy Networks (LLNs), the sensing or perception layer is based
on the IEEE 802.15.4 protocol. On the other hand, the network layer is based on the Routing Protocol for LLNs (RPL) that have
been standardised to fulfil the routing requirements in such networks. Both protocols suffer from security issues and lack
strong security solutions, especially in the field of trust management. In response to the above security issues, a new trust
management scheme has been introduced to address the MAC unfairness attacks against the IEEE 802.15.4 MAC layer.
Furthermore, a Metric-based RPL Trustworthiness Scheme (MRTS) has been proposed to enhance RPL security by introducing
a new trust metric and a new trust-based objective function, thus, rendering RPL more efficient in compromised networks.
Along this dissertation, MRTS went through three refinement versions, which were the subject of a succession of three
contributions. The efficiency of MRTS has been validated through extensive simulation experiments under different scenarios
using the open-source Contiki-Cooja simulator. The results demonstrate significant performance enhancements in terms of
routing security, power consumption, packet delivery ratio, and throughput. Besides, mathematical analyses prove that MRTS
meets the requirements of consistency, optimality, and loop-freeness and that the proposed trust-based routing metric has
the isotonicity and monotonicity properties required for a routing protocol. Furthermore, game theory mathematical analyses
and evolutionary simulation results show that MRTS, as a strategy, is an efficient approach in promoting the stability and the
evolution of IoT networks.
