Improving the Convergence Period of Adaptive Data Rate in a Long Range Wide Area Network for the Internet of Things Devices

Round 1

Reviewer 1 Report

The authors proposed a new ADR algorithm that is evaluated  through simulations.

The authors should also add details about the simulator, is an off the shelf software, is written end-to-end by the authors?

Can the proposed algorithm be applied to the cellular IoT techniques.

Also can the authors compare LoRa with the proposed algorithm with cellular IoT devices.

Can the proposed algorithm be applied in a real-world scenario, to be implemented in real device? Can the authors comment in the conclusions about this aspect.  

Author Response

Dear Reviewer

I am sending you the responses to your detail review on the submission Manuscript ID energies-1310023 entitled “Improving the Convergence Period of Adaptive Data Rate in Long Range Wide Area Network for the Internet of Things Devices”. First, we would like to thank the reviewer for their thoughtful comments. We the authors believe their comments would enhance the content of this manuscript. The responses are the following:

Reviewer #1: Comments:

The authors proposed a new ADR algorithm that is evaluated through simulations.

Comment #1: The authors should also add details about the simulator, is an off the shelf software, is written end-to-end by the authors?

Response: In this study, the simulator utilized in the experimental analysis was the LoRaWAN module in [1], wherein the MAC layer was modified to include implementation of the (1) mobility environment, (2) ADR protocol with modified frame header and (3) the proposed ADR.

Reference:

[1] Magrin, D., Capuzzo, M. and Zanella, A., 2019. A thorough study of LoRaWAN performance under different parameter settings. IEEE Internet of Things Journal, 7(1), pp.116-127.

Comment #2: Can the proposed algorithm be applied to the cellular IoT techniques.

Response: Generally, the proposed solution can be applied to any technology offering multi-data rate scenarios. Since the proposed scheme adjusts the data rates (also known as spreading factor) can be applied to cellular IoT (e.g., LET-M and NB-IoT) with slight modifications because of the underlying technology working and structure.

Response:

Comment #3: Also can the authors compare LoRa with the proposed algorithm with cellular IoT devices.

Response: Regarding the comparison, the cellular IoT variants are conceptually different from our proposed ADR. Therefore, a direct comparison with cellular IoT variants could not be possible because of the difference in the underlying technologies (i.e., NB-IoT devices does not support mobility). In contrast, our proposed ADR targets both SF and TP adjustments under the confirmed mode at both end device and networks server sides under mobility. Thus, we believe that cellular IoT is beyond the boundaries of our research paper. Finally, we remark that cellular IoT could potentially be used as another research work.

 

Response:

Comment #4: Can the proposed algorithm be applied in a real-world scenario, to be implemented in real device? Can the authors comment in the conclusions about this aspect.

Response: No, since the proposed ADR is implemented at the network server-side, it can be easily implemented at the network server-side only. Therefore, end device side firmware does not need to be changed.

We have added the following text in the revised version of the manuscript in the conclusions.

A snapshot from the revised version of the manuscript

 

Reviewer 2 Report

The paper is well written overall.  One item is that, although the abbreviations are defined before they are used, there are too many abbreviations. This makes it difficult for the reader to keep track of all of the items.  One recommendation is to periodically use the full names of the abbreviations periodically in the paper.

The authors present a new adaptive data rate scheme that is useful for end devices that are mobile or subject to shadowing.  Through simulation, the authors show improvement over previous methods for these types of environments.  The improvement is significant.

The use of both block diagrams and pseudocode to describe the algorithm contributes to the reader's understanding.

Figure 4 is a little difficult to understand and more explanation would benefit the paper.

 

 

 

 

 

 

Author Response

Dear Reviewer

Thanks for your comments. Our reply is attached herewith. 

 

Thanks

Author Response File: Author Response.pdf

Reviewer 3 Report

0. Summary:
This article proposes a novel Adaptive Data Rate (ADR) on the Network Server (NS) side to improve packet loss rate and increase coverage time when using Long-Range Wide Area Network (LoRaWAN).

I will point out some criticisms that I hope will be constructive in improving the article in future submissions.

1. Language and grammar
The authors of this article did a good job of writing it. Although my English grammar is not excellent, I believe that some sentences could be rewritten to improve the general understanding of the text. Some examples are lines 31-32.

2. Main Issues
a) Energy consumption is one of the results presented when using the proposed ADR. However, there is no related work presented on this metric (energy). I recommend adding it to the related work section.
 

3. Minor problems
a) Referral URL 2 is broken.
b) Furthermore, I believe that section 2 (related works) could be improved with recent articles on improvements and proposals for ADRs. Perhaps authors could present a comparison table or other method that would help the reader fully understand this subject's scientific contributions.

Author Response

Dear Reviewer

Thanks for your detail review. Our reply is attached herewith.

Best Regards

 

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.