Threat Vector–Hierarchical Attack Representation Model-Based Threat Modeling and Security Assessment for Satellite Networks

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Paper Summary

The paper "Hierarchical Threat Modeling and Security Assessment for Satellite Network" proposes a framework based on TV-HARM for hierarchical threat modeling and security assessment in satellite networks. The research emphasizes the need for more comprehensive approaches to deal with vulnerabilities distributed across different network segments (terrestrial, space, and user).

The methodology uses quantitative metrics to assess threats and the effectiveness of different countermeasures, such as OS Patch, Protocol Patch, and CFR. The experiments analyze four attack scenarios and demonstrate how the combined application of countermeasures can significantly reduce risks. However, the study does not explore the practical feasibility of implementing the model in real operational networks and lacks more direct experimental comparisons with competing approaches, such as Attack Graphs (AG) and Bayesian Attack Graphs (BAG).

The following are comments on the article:

Title

- The article's title is informative and represents the scope of the work well. However, to highlight the proposed innovation more clearly, it is suggested that a reference to the TV-HARM model be included, highlighting its specific application in the security of satellite networks.

 

Abstract

• Highlight the innovation, briefly comparing TV-HARM and other approaches, highlighting their specific advantages for satellite networks.
• Describe the experiments, including concise information about the scenarios analyzed and the main results obtained, making the summary more informative for the reader.

 

Introduction

• For the following sentence: Prior research has primarily focused on specific components or attack types, often emphasizing communication security [6,20].

- It is suggested that the specific challenges that previous models do not address satisfactorily be emphasized and detailed. To do this:

• Add a discussion on how previous approaches fail to consider aspects such as distributed attacks between segments (terrestrial, space, and user), interdependence of vulnerabilities, and lack of quantitative risk metrics.
• Explain how the proposed hierarchical approach overcomes these limitations and provides a more comprehensive security assessment.
• Mention previous studies and their specific limitations to illustrate the gaps better.

 

Section 3.4.1

• Mentions that TV-HARM is an extension of HARM, which integrates Attack Graphs (AG) and Attack Trees (AT) for attack vector analysis
• However, there is no explicit comparison between TV-HARM and other graphical models used for security modeling, such as Attack Graphs (AG), Bayesian Attack Graphs (BAG), and Markov Models.
  • Include a brief explanation of these models and their applications in threat modeling.
  • Directly compare TV-HARM with these approaches, highlighting its advantages in hierarchical modeling and analyzing vulnerability interdependence.
  • Cite previous studies that used graphical models for security analysis in satellite networks, highlighting their limitations and how TV-HARM overcomes them.

 

Section 3.4.2

- Approach to Satellite Network (338 to 343):

• Excerpt: "We propose modified equations that build upon the foundational structure of TV-HARM by incorporating protocol vulnerabilities (𝑝𝑣1, 𝑝𝑣2, . . . ), addressing the limitations of the existing model and enhancing its applicability to satellite networks. This extension, grounded in Definition 4, provides a comprehensive framework for analyzing threat elements by integrating protocol vulnerabilities, enabling more accurate interaction analysis between attack paths and vulnerabilities."
• Include a more detailed explanation of the modifications made to the model to deal with satellite networks' particularities, such as the integration of specific satellite protocol vulnerabilities and multi-segment threats (terrestrial, space, user).
• Compare the differences between the original version of HARM and the TV-HARM version adjusted for satellites, specifying the benefits of the modified approach.

 

 

Section 4.3

• Attack Impact Metrics, in lines 632 to 652, where the authors evaluate how different strategies (OS Patch, Protocol Patch, Both Patch and CFR) impact network security.
• Include a more detailed comparison of how each strategy influences security metrics, illustrating the practical effects of the OS Patch, Protocol Patch, and Both Patch approaches.
• Include an example, highlighting a scenario from the paper in which each specific approach had the most significant impact on attack mitigation.

 

 

Conclusion

- The Conclusion section summarizes the main findings and reinforces the importance of systematic approaches to satellite network security. However, limitations are mentioned generically. Excerpt:

• "The proposed model provides a robust basis for future security assessments in satellite networks. By addressing emerging threats and refining mitigation strategies, this framework can support the development of advanced security solutions and contribute to strengthening the resilience of satellite communication systems."

-  In addition, section 4.4 - Discussion and Future Work, mentions future challenges, such as the need for validation in real operational networks and the application of AI for anomaly detection, but without in-depth details (further details on future work)

The following improvements are also suggested

1. Practical feasibility of countermeasures, including a brief discussion of the technical challenges and costs of implementing the proposed strategies (e.g., OS Patch, Protocol Patch, CFR) in real operational networks and specifying possible barriers to the adoption of TV-HARM in commercial or government scenarios.
2. Impact of the model on real operational networks: discuss how TV-HARM could be applied in real networks, considering constraints such as limited bandwidth, computational constraints onboard satellites, and real-time requirements, and include references to case studies or future work that can validate the model in operational networks.

Comments on the Quality of English Language

The English in the manuscript is generally clear and well-structured. However, some sentences could be refined for better readability and clarity. Minor grammatical adjustments and rewording in certain sections, particularly in the Introduction and Discussion, would enhance the overall flow of the text.

Author Response

We sincerely appreciate the reviewer’s thorough and insightful feedback on our manuscript.  
In response, we have carefully revised the manuscript to address all comments and have provided a detailed, point-by-point response outlining the specific changes made.  
For a comprehensive response, please refer to the attached document.  

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The research addresses a highly relevant and timely topic in the field of cybersecurity applied to satellite networks, filling a gap in the literature, as previous studies tend to overlook a comprehensive approach. Although the methods are well-structured, it is suggested that they be described in greater detail, particularly regarding the practical implementation of the TV-HARM model and the selection of evaluation metrics. Clarifying how certain experimental data were obtained and how specific model parameters were defined would enhance the structure of the research. Additionally, it is recommended to elaborate further on the explanation of experimental procedures and provide a detailed account of the application of mitigation strategies, such as patch deployment. This would significantly improve the study's reproducibility and strengthen the validity of the presented results.

In the results section, it is recommended to deepen the discussion by highlighting the significance of the findings and their applicability in real-world contexts, such as the space industry or global cybersecurity policies. A critical discourse contrasting the reviewed literature with the experimental results is advised. This would enrich the conclusions and provide a more comprehensive understanding of the study’s contributions. Furthermore, it is suggested to detail the study’s limitations and outline possible directions for future research, particularly concerning the practical implementation of mitigation strategies in real-world scenarios.

Author Response

We sincerely appreciate the reviewer’s thorough and insightful feedback on our manuscript.  
In response, we have carefully revised the manuscript to address all comments and have provided a detailed, point-by-point response outlining the specific changes made.  
For a comprehensive response, please refer to the attached document.  

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

What is the architecture of the satellite communication proposed in your work? Describe the logical structure of the satellite network in your work.

No comparative analysis with literature reported results.

Describe the advantages of the network proposed by the authors. How were the data in Table 3 calculated? Especially for the TCP/IP protocol.

Does the author consider the topic original or relevant in the field? Does it address a specific gap in the field?

In Section 2, authors need to shed more light on their contributions. A more detailed explanation would help emphasize the significance of their work.

For each section, please try to insert a small introductory paragraph to introduce it.

Author Response

We sincerely appreciate the reviewer’s thorough and insightful feedback on our manuscript.  
In response, we have carefully revised the manuscript to address all comments and have provided a detailed, point-by-point response outlining the specific changes made.  
For a comprehensive response, please refer to the attached document.  

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

This paper investigates the impact of rain-induced amplitude and phase distortions on ultra-wideband communication systems using amplitude modulation. By analyzing radio links simulated with the Synthetic Storm Technique across different climatic regions, the study provides valuable insights into the effect of rain on signal integrity. The findings suggest that rain does not introduce significant linear distortions in millimeter-wave ultra-wideband channels, making this research a noteworthy contribution to the field.

Given its relevance and well-structured analysis, I recommend it for publication with the following minor improvements:

1. Reduce the frequent use of "we" throughout the manuscript to enhance readability and maintain a formal tone.
2. Consider adding a comparison table summarizing key results in relation to other studies or previous work. This would significantly enhance the clarity and impact of your findings.
3. Avoid including figure numbers or specific references in the conclusion. Instead, present a concise, standalone summary of the key takeaways from your study.

Author Response

We sincerely appreciate the reviewer’s thorough and insightful feedback on our manuscript.  
In response, we have carefully revised the manuscript to address all comments and have provided a detailed, point-by-point response outlining the specific changes made.  
For a comprehensive response, please refer to the attached document.  

Author Response File: Author Response.pdf