Delegated Proof of Secret Sharing: A Privacy-Preserving Consensus Protocol Based on Secure Multiparty Computation for IoT Environment +
Footnote †: Copyright: © 2022 by the authors. Licence MDP, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ([[https://creativecommons.org/licenses/by/4.0/](https://creativecommons.org/licenses/by/4.0/)]([https://creativecommons.org/licenses/by/4.0/](https://creativecommons.org/licenses/by/4.0/))). [PERSON]  
1 Department of Computer Science and Engineering, University of South Carolina, Columbia, SC 29208, USA; [EMAIL_ADDRESS]  
[PERSON]  
2 Air Force Research Laboratory, Rome, NY 13441, USA; [EMAIL_ADDRESS]  
[PERSON]  
1 Department of Computer Science and Engineering, University of South Carolina, Columbia, SC 29208, USA; [EMAIL_ADDRESS]  
Footnote 1: email: {[EMAIL_ADDRESS]}  
Footnote 2: email: {[EMAIL_ADDRESS]}  
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some countries with a population of more than 10 million, such as Argentina, Netherlands, and United Arab Emirates [4]. Unlike the PoW protocol, Proof of Stake (PoS) does not prompt extreme amounts of energy consumption. In PoS, the production of a new block is based on the amount of stake (coins in cryptocurrency) a participant holds [5]. The principle in the back is that the participant that holds the most stakes cherishes the worth of the blockchain network the most and is not willing to lose the wealth, so the probability that this participant is honest is quite high. However, an often discussed point about PoS is that it probably leads to the centralization of the blockchain network since the blockchain network utilizing PoS favors participants with a higher amount of stakes, and a more substantial participant will use the profit to increase the production ability of new blocks; thus, a more substantial participant grows faster than a participant with a smaller stake. After some point, the cost of entering the group of block producers becomes too high, causing many other participants to quit, resulting in centralization [6]. In addition to these two most popular consensus protocols, there are some other competitive ones, including Proof of Elapsed Time (PoET), Proof of Luck (PoL), and Delegated Proof of Stake (DPoS). Both PoET and PoL utilize the capacity of a Trusted Execution Environment (TEE), such as Intel's Software Guard Extension, to achieve consensus. PoET generates a random waiting time for each participant in the blockchain network, in which the one whose waiting time expires first will win the selection and obtain the privilege of producing a new block [7]. PoL makes all participants generate a random number in each round of block producing, and the participant with the largest time is the winner [8]. DPoS is a hybrid consensus protocol that utilizes the representative democratic. Nodes in the blockchain network can vote for a few delegates who are responsible for the network maintenance and new block packing. The Internet of Things (IoT) network has evolved because of the advancement of multiple techniques, including embedded systems, wireless sensors, and automation. IoT devices are widely adopted in the market of smart homes, healthcare systems, manufacturing, etc. However, there are many serious issues exposed along with the development of IoT ecology, especially in the areas of security and scalability. Security is a major concern for the center server and sensors at the edge of the IoT network. The center server of the IoT network is an obvious target of DDoS attacks, which have the potential to cause the paralysis of the entire network. Another issue is about the scalability. Along with the fast increase in the number of connected devices, the overhead of the authentication process, address assignment, and frequent communications will impose growing pressure on the center server.