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Title: ExTru: A Lightweight, Fast, and Secure Expirable Trust for the Internet of Things
The resource-constrained nature of the Internet of Things (IoT) edges, poses a challenge in designing a secure and high-performance communication for this family of devices. Although side-channel resistant ciphers (either block or stream) could guarantee the security of the communication, the energy intensive nature of these ciphers makes them undesirable for lightweight IoT solutions. In this paper, we introduce ExTru, an 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 these devices, it also consumes far less energy than the conventional side-channel resistant ciphers. Although the overall structure of the proposed scheme is leaky against physical attacks, 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 protect the communication against side-channel and scan-based attacks (e.g. SAT attack). Furthermore, we demonstrate that by properly configuring the value of T, ExTru more » not only increases the strength of security from per “device” to per “message”, it also significantly improves energy saving as well as throughput vs. an architecture that only uses a conventional side-channel resistant block/stream cipher. « less
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Award ID(s):
1718434 2200446
Publication Date:
Journal Name:
2020 IEEE 14th Dallas Circuits and Systems Conference (DCAS)
Page Range or eLocation-ID:
1 to 6
Sponsoring Org:
National Science Foundation
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