Notes in Computer Science, vol 12059., Cham, Springer,
2020, pp. 523-540.
[25] A. Hayes, "Proof of Capacity (Cryptocurrency),"
Investopedia, September 24, 2020.
[26] L. S. Sankar, S. M. and M. Sethumadhavan, "Survey of
Consensus Protocols on Blockchain Applications," in
2017 International Conference on Advanced Computing
and
Communication
Systems
(ICACCS
-2017),
Coimbatore, India, January 06 – 07, 2017.
[27] Z. Zheng, S. Xie, H. Dai, X. Chen and H. Wang, "An
Overview of Blockchain Technology: Architecture,
Consensus,
and Future Trends," in
IEEE 6th
International Congress on Big Data, June 2017.
[28] A. P. Joshi, M. Han and Y. Wang, "A survey on security
and privacy issues of blockchain technology,"
Mathematical Foundations of Computing, vol. 1, no. 2,
pp. 121-147, May 2018.
[29] X. Li, P. Jiang, T. Chen, X. Luo and Q. Wen, "A survey
on the security of blockchain systems,"
Future
Generation Computer Systems, vol. 107, pp. 841-853,
June 2020.
[30] E. J. d. Aguiar, B. S. Faiçal, B. Krishnamachari and J.
Ueyama, "A Survey of Blockchain-Based Strategies for
Healthcare,"
ACM Computing Surveys, vol. 53, no. 2, p.
27, March 2020.
[31] H. T. M. Gamage, H. D. Weerasinghe and N. G. J. Dias,
"A Survey on Blockchain Technology Concepts,
Applications, and Issues,"
SN Computer Science, vol. 1,
no. 114, 2020.
[32] D. Berdik, . S. Otoum, . N. Schmidt, D. Porter and Y.
Jararweh, "A Survey on Blockchain for Information
Systems Management and Security,"
Information
Processing and Management, vol. 58, no. 1, January
2021.
[33] S. King and S. Nadal, "PPCoin: Peer-to-Peer Crypto-
Currency with Proof-of-Stake,"
https://decred.org/research/king2012.pdf, August, 2012.
[34] Crushcrypto, "WHAT
IS DELEGATED PROOF-OF-
STAKE?," https://crushcrypto.com/what-is-delegated-
proof-of-stake/, 2021.
[35] D.
Schmidt,
"Delegated
Proof
of
Stake,"
https://www.benzinga.com/money/delegated-proof-of-
stake/, July, 2020.
[36] Intel Corporation, "PoET 1.0 Specification," Accessed
March 21, 2021 from
https://sawtooth.hyperledger.org/docs/core/releases/1.0/
architecture/poet.html, 2016.
[37] J. Frankenfield, "Proof of Elapsed Time (PoET)
(Cryptocurrency)," Investopedia, October 16, 2020.
[38] Academy Binance, "What Is
a Directed Acyclic Graph
(DAG) in Cryptocurrency?," Accessed March 21, 2021
from https://academy.binance.com/en/articles/what-is-a-
directed-acyclic-graph-dag-in-cryptocurrency.
[39] "IOTA,"
Accessed
March
23,
2021
from
https://www.iota.org/.
[40] R. Santos, K. Bennett and E. Lee, "Blockchain:
Understanding Its Uses and Implications," The Linux
Foundation, 2021.
[41] T. Kozak, "Consensus Protocols That Meet Different
Business Demands. Part I," intellectsoft, March 26,
2018.
[42] CrushCrypto, "WHAT IS PROOF OF WORK?,"
https://crushcrypto.com/what-is-proof-of-work/, 2021.
[43] CrushCrypto, "WHAT IS DELEGATED PROOF-OF-
STAKE?," Crushcrypto, 2021.
[44] CrushCrypto, "WHAT
IS PRACTICAL BYZANTINE
FAULT TOLERANCE (PBFT)?," Crushcrypto, 2021.
[45] S. Zhang and J.-H. Lee, "Analysis of the main consensus
protocols of blockchain,"
ICT Express, vol. 6, pp. 93-97,
2020.
[46] A. M. Antonopoulos, Mastering Bitcoin, 2nd Edition,
O'Reilly Media, Inc., June 2017.
[47] W. Chen, Z. Xu, S. Shi, Y. Zhao and J. Zhao, "A Survey
of Blockchain Applications in Different Domains," in