Cybersecurity in Intelligent Transportation Systems
Round 1
Reviewer 1 Report
This manuscript describes some general outlines of the ITS architecture and its security issues. The authors just introduce some conventional methods as network segmentation and cryptography that should be adapted in order to be applied in ITS cyber security. Although several innovative approaches are briefly mentioned in this manuscript, e.g.,block-chain, bloom filter, fog computing, artificial intelligence, game theory,and ontology. This manuscript unfortunately does not provide more explanations on these innovative approaches. This will result in the technical contribution of this manuscript is somewhat undefined.Author Response
Introductory paragraphs, which summarize and provide additional information on innovative approaches in ITS cybersecurity have been added in response to the remark (Lines 169-182 and 245-252). In Section 6, information on each of the innovative approaches is separated in a new subsection for better readability. The AI section (6.1) has been expanded. (Lines 254-256)
Reviewer 2 Report
The review submitted for the assessment relates only to the technical layer of ITS. I miss examples of specific security holes in specific ITSs. The lack of these examples means that the content of the review does not fully correspond to its title.
I would suggest supplementing this study with just these examples. Preferably in part devoted to discussion. Now, it is at a slightly different level of abstraction than the everyday use of the systems mentioned in the title.
Author Response
In response to the remark, the Discussions section has been revised. In order to facilitate the perception of the information, the explanations of the approaches to the implementation of cybersecurity have been moved so that they correspond to the issues and to the specific cyber attacks (the information summarized in the table). At the end of the section are given examples of specific ITS security systems that target specific cyberattacks - Lines 322 - 344. And two new references are added.
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.
Round 1
Reviewer 1 Report
The paper is a review of possible cybersecurity solutions for intelligent transportation systems at different architectural and functional layers of such systems.
The paper has several shortcomings:
- The introduction is rather short and does not really motivate the reader on what the current issues at the intersection of intelligent transportation systems and security is. The paper would be significantly improved with a lengthy introduction that cites current work and position papers referring to the new challenges these systems pose.
- Figure 1 is important but it is blurry and the caption does not really make any statement as to its importance. Suggestion: make a statement "The different layers composing intelligent transportation systems pose x, y, z challenges to security."
- A large number of citations seem to come out of nowhere, I am expecting that a review will detail the deep insight coming from the work being cited and not instead being cited in "passing".
- A review should target audience that wants to enter a field, the people already conducting cutting edge research already know what is included in a review. Therefore, a review's secondary purpose to providing a summary of important works is to define basic concepts. The paper omits such definitional discussions, for example, what is the "fog". This is but one example of a non-defined entity in the paper.
- A review should address the possible research directions. This is done implicitly here. These should be detailed in full.
As a side comment, the amount of works cited is too narrow and it is odd at list as a visual litmus test not to see works cited from leading conferences in the intelligent transportation systems area (for example, Intelligent Vehicles, IEEE ITSC, etc.)
I think the idea of the paper is good and the skeleton for a review is there. However, a lot more work needs to be done for this review to be useful to the research community. I hope the authors heavily edit this paper and try again to get this review out. There is definitely a _need_ for it, but this paper does not cover that need adequately.
Reviewer 2 Report
This study discussed ITS architecture and security issues. This paper is very interesting and meaningful in that it suggests a novel approach to secure ITS. The manuscript is well written and research topic, literature, and structure, everything is fine. However, the main contents and argument of this study is too general and in an early stage for a publication. All the core contents of the study are at the level of ideas, and for academic value, specific discussions or directions for each issue are required. Otherwise, it would be an alternative if the authors expand the conclusion of the study and discuss it as the core content in the manuscript. It is considered that the related content can be supplemented only by further research, and it is thought that quite long time will be needed for this.
Reviewer 3 Report
The simulation results are needed for analyzing security strength and performance criteria.
Reviewer 4 Report
This paper attempts to provide a set of related security work that can be used to solve ITS security challenges. However, the structure of the paper is not good, and they authors did not set the scene by listing a list of security challenges in ITS, and then relate how these security technologies can be used to solve them.
Section 2: Very generic security challenges for ITS described here. What are the threat models, what are the vulnerabilities, security attacks that could have occurred? The IoT architecture presented that the author claimed that could be applied to ITS is rather standard and abstract, high level.
Page 2, line 57: What is the exact recommendation of WAVE authentication mechanism?
Page 3, line 85: The table outlines the "comparison" of security issues, in my opinion, these layers should be working together to solve the security issues. There may be security issues at different layers, but that does not necessarily mean that the security issues can only be addressed within the layer itself.
Page 3, line 106: This section on Blockchain attempts to describe related work on MANET, routing, and blockchain. These related work seem to be independent from with other, with no effort from the authors to try to link them to ITS. I find that the description is not so related to AV or ITS.
Page 4, line 141: Could you please explain why is anonymous authentication is important in VANET?
Page 4, Section 4.3, 4.4: Bloom Filter, and Security by Contract, these are also very generic description and how are they related to ITS and VANET?
Page 5: Intelligent security in IoT. Would be good that the authors can relate some of these approaches to ITS, and they can be used to solve ITS security challenges.
