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abstract: 'The resource-constrained nature of the Internet of Things (IoT) devices, poses a challenge in designing a secure, reliable, and particularly high-performance communication for this family of devices. Although side-channel resistant ciphers (either block cipher or stream cipher) are the well-suited solution to establish a guaranteed secure communication, the *energy*-intensive nature of these ciphers makes them undesirable for particularly lightweight IoT solutions. In this paper, we introduce *ExTru*, a novel encrypted communication protocol based on stream ciphers that adds a configurable switching & toggling network (*CSTN*) to not only boost the performance of the communication in lightweight IoT devices, it also consumes far less energy compared with the conventional side-channel resistant ciphers. Although the overall structure of the proposed scheme is leaky against physical attacks, such as side-channel or new scan-based Boolean satisfiability (*SAT*) attack or algebraic attack, we introduce a dynamic encryption mechanism that removes this vulnerability. We demonstrate how each communicated message in the proposed scheme reduces the level of trust. Accordingly, since a specific number of messages, $N$, could break the communication and extract the key, by using the dynamic encryption mechanism, *ExTru* can re-initiate the level of trust periodically after $T$ messages where $T<N$, to 