Maritime Communications—Current State and the Future Potential with SDN and SDR
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe introduction of technologies such as unmanned aerial vehicles (uavs), autonomous underwater vehicles (auvs) and Internet of Ships (IoS) can improve the efficiency of maritime communications and maritime operations. They also bring new challenges in terms of security and network management. In this paper, the authors first review the current status and patterns of maritime communications. Then, software-defined radio (sdr) and software-defined networking (sdn), which are currently being adopted in the shipping industry, are reviewed and evaluated as enablers of the Internet of Things (IoS). The paper is readable and logically structured. However, the following points can be further improved:
(1) In Section 5.3, the authors analyze the performance of SDN-SDR-based SATCOM systems, but it seems to lack experimental validation.
(2) SDN technology itself can bring problems with system security, and the authors can discuss in this aspect.
(3) The format of references [9],[43][44] seems to be irregular.
Author Response
We really appreciate for your feedbacks. Your comments were helpful for us.
Response #1: In this paper, our primary objective is to present a conceptually feasible unified SDN-SDR cross-layer communications framework for the Maritime industry. In section 5.5, we have presented the theoretical underpinnings along with a non-trivial example for the expected performance improvement of the proposed framework over purely SATCOM communications in light of a Geo-synchronous satellite. Our work shows an analytical approach that indicates the feasibility of our overall framework. Experimental validation will be implemented in subsequent work. The next step of this project is to implement a working prototype testbed with COTS (Commercially Off The Shelf) SDN and SDR hardware. The prototype implementation will take into consideration various environmental factors along with different types of satellites (LEO, MEO, GEO) to empirically validate the robustness of the proposed framework in contested and resource constrained Maritime environment. At the time of this article submission, we are in possession of some of the required hardware and software, and prototype implementation is impending.
Respond #2: SDN, while offering unprecedented flexibility and efficiency in network management, can introduce challenges to system security. The centralization of control in SDN architectures creates a potential single point of failure, making the network vulnerable to targeted attacks. Additionally, the programmability of SDN controllers opens up new attack vectors, as malicious actors may exploit vulnerabilities in the software-defined infrastructure to manipulate network behavior. Moreover, the separation of the control plane from the data plane in SDN can expose communication channels between these components to security risks, potentially leading to unauthorized access or data breaches. As organizations increasingly adopt SDN to enhance their network capabilities, it becomes imperative to address these security concerns through robust encryption, access controls, and continuous monitoring to safeguard the integrity and confidentiality of network operations.
Respond #3: We fixed the issue of references.
Reviewer 2 Report
Comments and Suggestions for AuthorsThis paper talks about UAV, MTS and SDN and talks about the security challenges . The technical methodology seems reasonable. I recommend the authors revise it according to following points:
a) It is suggested to make clearer summary to contributions of this paper.
b) The framework need to be discussed in detail.
c) It would be better if abstract can be revised based on the findings.
d) It is suggested to give more simulation results for evaluation.
e) The data source is not clear. Please give more description for it.
f) The first part of the introduction (until the beginning of p. 2) fails to describe the role played by cities in such a debate and therefore into your research.
g) Conversely to what you wrote in the abstract the manuscript seems to consider the econometric model as the basis.
h) The description of the research contexts should be moved to the section describing research aim and method.
i) Related study section needs a table that discuss the pros and cons of existing work. There are many research article that have used AI and blockchain together. Author should include such articles ; Blockchain and deep learning empowered secure data sharing framework for softwarized UAVs: P2IDF: A privacy-preserving based intrusion detection framework for software defined Internet of Things-fog (SDIoT-Fog); DLTIF: Deep learning-driven cyber threat intelligence modeling and identification framework in IoT-enabled maritime transportation systems
j) You often refer to 'relevant' scholars. How to consider them this way and why they are relevant while others are not?
Comments on the Quality of English LanguageNeeds moderate changes
Author Response
We really appreciate your feedback.
Respond to a: In this paper, our primary objective is to present a conceptually feasible unified SDN-SDR cross-layer communications framework for the Maritime industry. In section 5.5, we have presented the theoretical underpinnings along with a non-trivial example for the expected performance improvement of the proposed framework over purely SATCOM communications in light of a Geo-synchronous satellite. Our work shows an analytical approach that indicates the feasibility of our overall framework. Experimental validation will be implemented in subsequent work. The next step of this project is to implement a working prototype testbed with COTS (Commercially Off The Shelf) SDN and SDR hardware. The prototype implementation will take into consideration various environmental factors along with different types of satellites (LEO, MEO, GEO) to empirically validate the robustness of the proposed framework in contested and resource constrained Maritime environment.
Respond to b: We discussed the details of framework in section 5.
Respond to c: We have revised the abstract to address this concern.
Respond to d and e: In this paper, our primary objective is to present a conceptually feasible unified SDN-SDR cross-layer communications framework for the Maritime industry. In section 5.5, we have presented the theoretical underpinnings along with a non-trivial example for the expected performance improvement of the proposed framework over purely SATCOM communications in light of a Geo-synchronous satellite. Our work shows an analytical approach that indicates the feasibility of our overall framework. Experimental validation will be implemented in subsequent work. The next step of this project is to implement a working prototype testbed with COTS (Commercially Off The Shelf) SDN and SDR hardware. The prototype implementation will take into consideration various environmental factors along with different types of satellites (LEO, MEO, GEO) to empirically validate the robustness of the proposed framework in contested and resource constrained Maritime environment. At the time of this article submission, we are in possession of some of the required hardware and software, and prototype implementation is impending.
Respond to f: We have addressed this issue in the revised version.
Respond to g: We have revised the abstract to address this concern.
Respond i: We have a plan to review papers regarding blockchain and deep learning approaches in the extension version of this paper.
Respond to j: Sorry, we did not get what is your question. Can you please elaborate it a little?
Thanks
Reviewer 3 Report
Comments and Suggestions for AuthorsPlease see the attachment.
Comments for author File: 
Comments.pdf
English language are fit for a research article, although some minor mistakes have been spotted, as shown in the report attached.
Author Response
Hi,
We really appreciate your feedback. We took into accounts your comments. Please consider the revised version. We highlighted the revision part in red color.
