Round 1

Reviewer 1 Report

In this paper, the authors proposed a new method for IoMT on blockchain. Although the idea is interesting, here are few suggestions:

(1) The experiment setting will need to be clarified. For example, which blockchain platform did your implementation based on? How many nodes? What are the statistics of the data being stored?

(2) Also, it would be better to refer to blockchain platform review papers such as [1][2][3], and discuss about the rationale of your chose of blockchain platform.

(3) Next, did you also implemented all the comparison methods shown in Figure 4 and 5? If so, please explicitly mention that and also provide their experiment settings.

(4) Finally, a thorough proofreading may be required, for example, "finical" --> "financial".

References:

[1] Macdonald M, Liu-Thorrold L, Julien R. The blockchain: A comparison of platforms and their uses beyond bitcoin. Work. Pap. 2017:1-8.

[2] Yu H, Sun H, Wu D, Kuo TT. Comparison of smart contract blockchains for healthcare applications. InAMIA Annual Symposium Proceedings 2019 (Vol. 2019, p. 1266). American Medical Informatics Association.

[3] Chowdhury MJM, Ferdous MS, Biswas K, et al. A comparative analysis of distributed ledger technology platforms. IEEE Access 2019; 7: 167930-43.

Author Response

Response to Reviewer 1 Comments

Point 1: The experiment setting will need to be clarified. For example, which blockchain platform did your implementation based on? How many nodes? What are the statistics of the data being stored?

Response 1: We thank the reviewer for pointing this out. We added the contribution to our paper. In our contribution section, we show that we use the Ethereum platform.

((Please see Page 2 (lines 74: 84), where the objective of our paper is added as follow :-))

So, the objectives of our paper are:

Implement a medical blockchain model using the Ethereum blockchain platform.
Modify the Ethereum blockchain by using SHA-256 as a hash function.
Modify the SHA-256 hash algorithm by using the LZ4 algorithm to speed up the process of creating blocks.
Modify the SHA-256 hash algorithm by preventing the hash code from starting with 0 to speed up the process of creating blocks.
Implement an authentication parties technique to complete transactions after verifying the patient and doctor's identities.

We create one block for each transaction between the patient and the doctor. So, the number of nodes depends on the number of transactions that may happen. This means that many blocks are created. We intend to solve this problem in our future work. So, we added it as future work.

((Please see Page 13 ( lines 405 : 407), where we modified in our futue work as follow :-))

We also intend to decrease the number of blocks by storing the information between the same doctor and the same patient in the same block.

Each block contains a wealth of information. This information is stored as an entry. So, if we have five sensors and each sensor measures a specific value, we will have five entries in that block.

Point 2: Also, it would be better to refer to blockchain platform review papers such as [1][2][3], and discuss about the rationale of your chose of blockchain platform.

References:

[1] Macdonald M, Liu-Thorrold L, Julien R. The blockchain: A comparison of platforms and their uses beyond bitcoin. Work. Pap. 2017:1-8.

[3] Chowdhury MJM, Ferdous MS, Biswas K, et al. A comparative analysis of distributed ledger technology platforms. IEEE Access 2019; 7: 167930-43.

Response 2: We thank the reviewer for pointing this out. We added the following three references::

((Please see Page 4 and 5 (Lines 127: 145) where we added the three references as follow:-))

Macdonald et al. [17] discussed how the blockchain could use in Bitcoin. They also compared between Ethereum, IBM Open Blockchain, Intel Sawtooth Lake, Blockstream Sidechain Elements, and Eris blockchain platforms based on many factors, such as usability, scalability, security, and feasibility. Their comparison showed that Ethereum is the best-suited one.

Yu et al. [18] carried out a practical comparison between Ethereum, Hyperledger Fabric, and MultiChain blockchain platforms. Their compassion is limited to compare the blockchain methods that contain a smart contract system. This comparison showed that the implemented application determines the best platform to use (e.g., maintenance for Ethereum, fine-grained access control for Hyperledger Fabric, and rapid development for MultiChain). The authors also suggested using a blockchain technology in the biomedical and healthcare sectors to reduce the probability of data theft.

Chowdhury et al. [19] presented a comparative analysis of various blockchain platforms. The authors compared 11 blockchain platforms. They used quantitative and qualitative analysis to help developers choose the best blockchain platform. The results of their analysis prove that Hyperledger Burrow lacks comprehensive documentation. As a result, the authors advised against using it. Their results also show that the Fabric platform was robust and that Sawtooth offered the best level of security.

Point 3: Next, did you also implemented all the comparison methods shown in Figure 4 and 5? If so, please explicitly mention that and also provide their experiment settings.

Response 4: Figure 4 and Figure 5 show the results of new experiments using the same experimental settings to compare these methods with the proposed system.

((Please see Page 11 (Lines 370: 372), where we added a paragraph to show that we reimplemented all the comparison methods as follow :-))

Figure 4 and Figure 5 show the results of new experiments using the same experimental settings to compare these methods with the proposed system.

Point 4: Finally, a thorough proofreading may be required, for example, "finical" --> "financial".

Response 4: We thank the reviewer for catching this error. We modified the finical word to the financial word. We also revise our paper.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript needs the changes before further decision.

What is the novelty of the paper, the paper needs to possess better originality and mention how this paper is more unique and be beneficial for future research.

Cite some recent works regarding this study?

Highlight some major contributions of the paper and also add paper organization.

Demonstrate the robustness and dependability.

Also see the following papers and try to strengthen the literature

https://doi.org/10.1155/2021/7608296

https://doi.org/10.1111/exsy.12978

Author Response

Response to Reviewer 2 Comments

Point 1: What is the novelty of the paper, the paper needs to possess better originality and mention how this paper is more unique and be beneficial for future research.

Response 1: We thank the reviewer for pointing this out. We added the contribution to our paper.

((Please see Page 2 (Lnes 74 : 84), where the objective of our paper is added as follow :-))

So, the objectives of our paper are:

Implement a medical blockchain model using the Ethereum blockchain platform.
Modify the Ethereum blockchain using SHA-256 as a hash function.
Modify the SHA-256 hash algorithm using LZ4 algorithm to speed up the process of creating blocks.
Modify the SHA-256 hash algorithm by preventing the hash code from starting with 0 to speed up the process of creating blocks.
Implement an authentication parties technique to complete transactions after verifying the patient and doctor's identities.

Point 2: Cite some recent works regarding this study?

Also see the following papers and try to strengthen the literature

https://doi.org/10.1155/2021/7608296

https://doi.org/10.1111/exsy.12978

Response 1: We added two new related work.

((Please see Page 5 (Lines 207: 214), where we added new relaeted work as follow:-))

Also, there are some recent works that built a blockchain system with the aid of a DL learning algorithm. For example, Kumar et al. [30] developed a security system using blockchain and DL algorithm. They used an Ethereum blockchain model to store the medical data, Stacked Sparse Variational Autoencoder (SSVA) algorithm to transform the medical data into any form readable by the computer, and the Self-Attention-Based Bidirectional Long Short-term memory (SABBLS) algorithm to detect any attack type. They used IoT-Botnet and TON-IoT datasets to ensure the security of their system. The results show that their method performed better than all previous methods.

((Please see Page 4 (Llines 147: 151), where we added new relaeted work as follow:-))

Rupa et al. [20] proposed an IoT system that monitors and manages the automated vehicle. They developed a blockchain system to secure and store the data collected from the IoT system. They created a new block to store the data. Therefore, they used the SHA-1 algorithm to hash the new block and connected it with the previous block.

We also added the first reference as a related work

((Please see Page 3, (Lines 122: 126) where we added a new relaeted work as follow:-))

Ratta et al. [16] discussed the role of using blockchain versions IoT technology to improve healthcare applications. The authors showed that they could use IoT and blockchain in the healthcare system in three key areas: remote patient monitoring, medication traceability, and medical record management. Also, they mention the difficulties that face IoT and blockchain in healthcare systems.

We also added the second reference as a related work

((Please see page 5, lines 194:200 where we added a new relaeted work as follow:-))

Mehbodniya et al. [28] developed a security framework based on the blockchain model. The authors used a modified Lamport Merkle digital signature technique to hash a new block. They used a Central Healthcare Controller (CHC) to perform authentication and verification as well as know who created the signature. The signature must be verified using the validation hash of the public key and the create key. Their results shoed that their proposed method is more effective, affordable, and quick.

Point 3 Highlight some major contributions of the paper and also add paper organization.

Response 1: We thank the reviewer for pointing this out. We added the contribution to our paper.

((Please see Page 2 (Lines 74 : 84), where the objective of our paper is added as follow :-))

So, the objectives of our paper are:

Implement a medical blockchain model using the Ethereum blockchain platform.
Modify the Ethereum blockchain by using SHA-256 as a hash function.
Modify the SHA-256 hash algorithm by using the LZ4 algorithm to speed up the process of creating blocks.
Modify the SHA-256 hash algorithm by preventing the hash code from starting with 0 to speed up the process of creating blocks.
Implement an authentication parties technique to complete transactions after verifying the patient and doctor's identities.

The organization of the paper is already exist in the paper. We also highlight the structure of our paper.

((Please see Page 2 (Lines 85 : 87), where the objective of our paper is added as follow :-))

The structure of this paper is as follows: Section 2 discusses some background and related work, Section 3 presents the proposed work, Section 4 presents the experimentations and its results, and Section 5 introduces the conclusion of the paper.

Point 4: Demonstrate the robustness and dependability.

We thank the reviewer for pointing this out. We added a new paragraph in the discussion section that proves that our method is robust and dependable.

((Please see Page 11 (Lines 331: 343), where the new paragraph is added as follow :-))

The robustness of blockchain is measured by four attributes [31]. The four characteristics of blockchain robustness are the hashing code cannot be reversed, blocks must be linked together, a consensus algorithm exists, and the blockchains are decentralized. We showed that our proposed method used a modified SHA-256 hash function algorithm. This function produces a hash code that can't be reversed. Also, we proved that the hash function hashed the transaction information and previous block hash code together, so our blockchain linked the blocks together. The proposed system used an Ethereum blockchain platform that used Proof of Stake as a default consensus algorithm. Finally, the proposed blockchain used a distributed ledger, in which it means that it is decentralized. Therefore, this proposed blockchain method is more robust. The proposed method used an authentication parties technique that checks the individuals' identities before they can access the data. We also show that it is very difficult to change any block information. This means that the proposed method is dependable.

Author Response File: Author Response.pdf

Reviewer 3 Report

Please see attached

Comments for author File: Comments.pdf

Author Response

Response to Reviewer 3 Comments

Point 1: Highlight your novelty. The contribution is not clear. Specify implemented blockchain

system specifications in regards its type, wallet details, consensus, etc

Response 1: We thank the reviewer for pointing this out. We added the contribution to our paper. Our objectives of the paper show that we use the Ethereum platform that uses Proof of Stake as a default consensus algorithm.

((Please see Page 2 (Lines 74: 84 where the objective of our paper is added as follow:-))

So, the objectives of our paper are:

Implement a medical blockchain model using the Ethereum blockchain platform.
Modify the Ethereum blockchain by using SHA-256 as a hash function.
Modify the SHA-256 hash algorithm by using the LZ4 algorithm to speed up the process of creating blocks.
Modify the SHA-256 hash algorithm by preventing the hash code from starting with 0 to speed up the process of creating blocks.
Implement an authentication parties technique to complete transactions after verifying the patient and doctor's identities.

Point 2: Add a table for section 2 containing the limitation of existing works on medical data preservation over a blockchain.

Response 2: We thank the reviewer for his feedback. We added the limitation of existing works at the end of Section 2.

((Please see Page 5 (Lines 215: 219), where the objective of our paper is added as follow:-))

All current works contain several flaws. They based their approach on the Ethereum blockchain without any modification to it. As a result, creating blocks requires extra time in their system. Additionally, they developed their security mechanism without requiring authentication of the two parties to the transaction. As a result, hackers could be able to impersonate patients or doctors.

Point 3: In line 183, What is entry (D) in this work? Fig 2 shows that an unique block will be created for every patient treatment. If it is the case, so many blocks required per hospital.

Response 3: Each block contains a wealth of information. This information is stored as an entry. So, if we have five sensors and each sensor measures a specific value, we will have five entries in that block. A new block is created for each transaction, so many blocks are created. We intend to solve this problem in our future work. So, we added it as future work.

(Please see Page 13 (Lines 405: 407), where we modified our future work as follow:-))

We also intend to decrease the number of blocks by storing the information between the same doctor and the same patient in the same block.

Point 4: In Line no 194, mentioned that “hash of a block”, is it hash of a block or hash of a

transaction? What do authors means of a block? What has been maintained in the block

transactions here?

Response 4: We produce a hash code for the new block (not for the transaction). The transaction information is stored in a new block. We then combine the transaction information, time stamp, and previous block hash code together. Therefore, we hash this combination using our proposed method to get the new block hash code.

Point 5: In algo 1, mentioned that TIi ( Transaction) as an output that maintains secure vital

signs. Then in line no 209, mentioned that “creates a new block by adding vital signs

and hashing the code of the new block”. Justify

Response 5: We apologized for that error. The output of Algorithm 1 is the hash code of the block.

((Please see Page 7 (Algorithm1), where we modified the output of the algorithm:-))

Point 6: Table 10 shows that blockchain 1.0, 2.0 and 3.0. Needs to mention the specifications of

those system.

Response 6: We already described them in the background section.

((Please see Page 3 (Lines 105:120), where we highlight the descrbtion of three blockchain versions as follow:-))

Blockchain Version 1.0 is utilized in payments and digital currency [13]. Version 1.0 of BlockChain had a flaw in that mining Bitcoin was wasteful and wasn't scalable, which led to the release of the updated version. Therefore, Blockchain Version 2.0 had been improved to solve the problems of blockchain Version 1.0. This version of the blockchain supports smart contracts and simple cryptocurrencies. Small Contracts are hence Little Computers that reside in Chains of Blocks. These little computers run free software that automatically checks the earlier established conditions, such as facilitation, verification, or enforcement, and lowers transaction costs. Ethereum has supplanted Bitcoin in Blockchain Version 2.0 [14]. As a result, Blockchain Version 2.0 processed many transactions quickly on the public network.

Blockchain Version 3.0 is based on features called Decentralized Apps (DApps). A DApp is similar to a regular app in that it may have a frontend written in any language that calls its backend, and that code runs on a decentralized peer-to-peer network in the backend. It uses decentralized communication and storage methods, such as Ethereum Swarm. Numerous decentralized applications exist, including BitMessage, BitTorrent, Tor, and Popcorn [15].

Point 7: Suggesting recent medical data preservation over a blockchain related works for your

considerations.

https://doi.org/10.3390/electronics11152314
10.1109/TII.2022.3161631
https://doi.org/10.1007/978-3-030-67540-0_36

Response 7: The first reference, we already added it in our paper.

((Please see Page 4 (Lines 163: 170), where we highlight the system that develobed by karti et al. as follow:-))

Ktari et al. [24] offered a platform built on IoT that enables patient health monitoring. They employed Blockchain as a safe method to secure patient data. They collected the medical data from several intelligent sensors, including blood pressure, SPO2 levels, and EEG signals. These data are collected by a Raspberry PI 4 embedded platform that serves as a smart data relay, processed on a backend server, and finally saved in a Blockchain embedded node. The preliminary findings demonstrate the platform's efficacy as a potential low-cost example of a protected Electronic Health Record (EHR).

We added the second reference as related work.

((Please see Page 5 (Lines 207: 214), where we added new relaeted work as follow:-))

We added the third reference as related work.

((Please see Page 4 (Lines 147: 151), where we added new relaeted work as follow:-))

Round 2

Reviewer 1 Report

The authors have addressed all my previous comments.

Reviewer 2 Report

The authors have submitted the revised paper by addressing all my concerns. I accept it

Reviewer 3 Report

The authors refined the manuscript as per the suggested comments.

Review Reports

Response to Reviewer 1 Comments

Response to Reviewer 2 Comments

Response to Reviewer 3 Comments