A Multi-Gateway Behaviour Study for Traffic-Oriented LoRaWAN Deployment

Round 1

Reviewer 1 Report

The goal of this paper, as exposed by the authors, is to present a study of factors impacting the LoRaWAN QoS in the case of multiple gateways usage.

Please Quantify the main results in the abstract and conclusion sections.

Figure 1 needs to be improved by adding additional information (OSI layers), and figure 2 can be explained in more detail. On which OSI layer is ALOHA implemented? What functions are implemented compared to CSMA/CD? Abbreviations must be presented when they are used for the first time in the article. The authors must consider additional experimental results situations based on traffic congestion, hardware&software constraints or different QoS scenarios.

Can a comparison be presented between the results obtained for A-PDR and LPI? The authors should clearly the personal contributions for THIS paper compared to previous research papers.

The reference section is good, citing new and relevant articles in the research area.

Author Response

Please see attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

In this manuscript, the authors present a parameters study of the multi-gateway usage in LoRaWAN under high-traffic conditions. They use extended simulation results to demonstrate that the use of several gateways can improve the network QoS. The presented work is interesting and very comprehensive, the quality of the manuscript is good and the references are appropriate. I therefore recommend this manuscript for publication.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

The paper discusses an interesting topic by studying different factors that impacting the LoRaWAN QoS where multiple gateways are used in a particular network. The paper includes some strong and other weak points that need to be addressed. 

 Strong Points

• The paper is well-structured and well-written.
• The abstract is well organized; it includes an introduction to the topic and the purpose of this study. In addition, it discusses the simulation parameters are used in this work, and then it ends with the findings.
• The conclusion gives a good direction into the future vision.
• The literature review section includes appropriate topics that are relevant to this study.

 Weak Points

• In the abstract, it is mentioned, “increasing the number of gateways ensures a better PDR…...”; however, the paper mainly represents the obtained results according to the A-PDR. 
• Are there any differences between A-PDR and PDR? 
• Why is PDR mentioned in the abstract as the primary research goal?
• The authors present the outcomes of the simulation utilizing the NS-3 simulator; nevertheless, the network topology that explains how the two or five gateways scenarios are connected for the study experiments is not clearly described.
• In the introduction section, it is mentioned that “However, such a solution will not work in all cases since many…..”, please give some examples of cases that the solution (i.e., improve the LoRaWAN QoS) should not be applicable.
• There is no comparative study between this work and other related works to ensure its superiority and validity.
• The introduction section mentions two research questions; it would be great if the authors refer to the main contribution and outcome sections that answer these two questions. 

 Some other remarks:

• There are some abbreviations in the paper, where no clear meaning of what these are stand for, such as the following:

• CAPEX
• OPEX
• P-LOHA
• …….
• Some table legends are above, and others are below tables; please check that. 
• Please give a short description for section 4.2. 
• I cannot find figure 2 in reference 5; please check that.

Author Response

Please see attachment.

Author Response File: Author Response.pdf