Routing Algorithm Based on Trajectory Prediction in Opportunistic Networks

Round 1

Reviewer 1 Report

In this manuscript entitled "Routing Algorithm based on Trajectory Prediction in Opportunistic Networks" the authors present RATP, a routing algorithm based on trajectory prediction. The article

provides sufficient background and include all relevant references. The research design sounds appropriate and the the conclusions seem supported by the results.

I thank the authors for this nice reading of the manuscript.  Some minor comments:

- The authors should not talk about "Data delivery mode". Delivery is the action of deciding that the message is intended for a certain node and providing the payload of the message to an application of a given node. I think the authors are confusing the terms routing/forwarding and delivery.

- Please, review the grammar of the article. There are several errors such as for example: "energy efficiency, The core idea". 

Author Response

1.    Reviewer: #1

 

Comments：

 

In this manuscript entitled "Routing Algorithm based on Trajectory Prediction in Opportunistic Networks" the authors present RATP, a routing algorithm based on trajectory prediction. The article provides sufficient background and include all relevant references. The research design sounds appropriate and the conclusions seem supported by the results. 

 

I thank the authors for this nice reading of the manuscript.  Some minor comments:

1. The authors should not talk about "Data delivery mode". Delivery is the action of deciding that the message is intended for a certain node and providing the payload of the message to an application of a given node. I think the authors are confusing the terms routing/forwarding and delivery. 

 

2. Please, review the grammar of the article. There are several errors such as for example: "energy efficiency, The core idea". 

Response 1

 

 I am very pleased that you appreciate our works. I am also honored you are my reviewer. Many thanks.

 

1. The authors should not talk about "Data delivery mode". Delivery is the action of deciding that the message is intended for a certain node and providing the payload of the message to an application of a given node. I think the authors are confusing the terms routing/forwarding and delivery. 

 

A: Thank you for reviewer’s comment. We are very pleased that reviewer points our weakness in manuscript. Many thanks. According to read your comments, we redesign the model name and changed it to ‘Data forwarding model’.

 

2. Please, review the grammar of the article. There are several errors such as for example: "energy efficiency, the core idea". 

 

A: We are so sorry that we made some grammatical and presentation errors although we revised the manuscript in this revision. We have carefully corrected the problems in this paper and substantially revised its style and presentation. A great number of errors have been revised. All the revised contents have been marked “in blue”.

 

Finally, we are very thankful your comment to revise our manuscript. Thank you again for reviewing our paper. Your comments have considerably assisted us in improving the quality of our paper. I hope that our work this time is satisfactory.

Reviewer 2 Report

The authors propose a new routing mechanism which exploits the trajectory prediction and can adapt to the network link quality instability in a fast manner, while considering the dynamic changes of the network topology.

The topic of the paper is very interesting, especially with the growing number of wireless connected devices in the nowadays networks. Overall, the paper is well-written and easy to follow and the authors have well-thought-out the main components to build the routing mechanism.

The authors should address the following comments to further improve the quality of their paper and its presentation.

-Initially, in the related work, the authors should capture the main research works exploiting the nodes’ characteristics to improve the information transmission among them.

-Those characteristics can be identified as the nodes’ mobility (e.g., "Adaptive clustering for mobile wireless networks." IEEE Journal on Selected areas in Communications 15, no. 7 (1997): 1265-1275, "Routing in clustered multihop, mobile wireless networks with fading channel." In proceedings of IEEE SICON, vol. 97, no. 1997, pp. 197-211. 1997) and the communication interest among them (e.g., "Interest-aware energy collection & resource management in machine to machine communications." Ad Hoc Networks 68 (2018): 48-57, "Interest, energy and physical-aware coalition formation and resource allocation in smart IoT applications." In Information Sciences and Systems (CISS), 2017 51st Annual Conference on, pp. 1-6. IEEE, 2017).

The authors should appropriately revise the provided literature review and update the references list accordingly.

-Moreover, in Section 3.1.3, the authors provide only the node location in a two dimensions plane. However, the nodes nowadays are also characterized by their third dimension, e.g., nodes in UAVs, drones, fully autonomous aerial systems, etc. The authors should better justify the introduced node location model.

-Moreover, in Section 3.2, it not clear how the authors determined the values of the \tau_a-c parameters. What is their physical meaning?

-Also, in Section 3.3, the authors should provide the detailed complexity analysis, as it is not evident how they concluded to the presented complexity of the routing mechanism.

  

Author Response

Dear reviewers and editor,

We are very grateful to the reviewers and the editor of the paper for their critical reading of the manuscript and their valuable suggestions for the paper’s further improvement.

We have checked the manuscript and revised it according to the comments. The following content is a point-to-point response to the reviewers’ comments.

See the attachment for details.

  Sincerely yours,

Author Response File: Author Response.pdf

Reviewer 3 Report

The paper proposes a routing algorithm for opportunistic networks based on trajectory prediction. The paper is interesting and generally well written. However, some issues have to be clarified/solved:

1. There are some unclear sentences that must be rewritten: the sentence from lines 77-80 (“The data transmission…”); line 84 (“The remaining parts … are mainly composed of the following parts”); the sentence from lines 113-114 (“DREMA …”); the sentence from lines 125-126 (“GEAR …”); the sentence from lines 132-133 (“Query the network …”); the sentence from lines 182-184 (“ Using the Gauss…”); the sentence from lines 260-261 (“According…”)

2. Lines 141-142: What the authors mean by “coordinating the differences”?

3. There might be some problems with eq. (1), because this limit can be infinity. In this situation, what happens with eq. (2)?

4. Lines 160-161: Based on previous two lines we cannot draw the conclusion that a Gaussian distribution can be selected as claimed by the sentence (“So it can be assumed…”).

5. Velocities are vectors and not scalars. Treating the vectors as scalars (considering only their magnitudes) like in this paper needs to be carefully explained.

6. The notation used right at the end of line 192 must be explained.

7. Line 244: From where these parameter values (0.8, 0.1 and 0.1) come from? Some details are needed.

8. Line 272: Instead of the classical big-O notation it is used “o”.

9. Eq. (22): how the distance real_j - pred_j is computed? Is it Euclidean distance? Normally real and pred have two components (on x and y axis).

10. The sentence (”Therefore …”) started in line 307 is confusing and must be reshaped.

11. In line 320 it is written “although CHBPR it has a high delivery ratio” instead of “although CHBPR has a high delivery ratio”.

12. What the authors mean by “the continuity between nodes increases” (lines 341-342)?

13. The last two sentences from the first paragraph (lines 375-377) of subsection 4.2.4 must be reshaped.

14. In my view, the authors can specify that there method may be easily extended for vehicular ad hoc networks – VANETs (“A tutorial survey on vehicular ad hoc networks” DOI: 10.1109/MCOM.2008.4539481), or wireless sensor, actuator and robot networks WSARNs (“Towards wireless sensor, actuator and robot networks” doi: 10.1016/j.jnca.2016.01.013).

15. The computations needed to predict the next location of sensor nodes may take too long (Gaussian processes) and in the meanwhile the forwarding path towards destination node may already disappear (the nodes are moving in this time interval so a decision to forward packets to a specific node may not be actual). Some clarifications are needed.

Author Response

Dear reviewers and editor,

We are very grateful to the reviewers and the editor of the paper for their critical reading of the manuscript and their valuable suggestions for the paper’s further improvement.

We have checked the manuscript and revised it according to the comments. The following content is a point-to-point response to the reviewers’ comments.

See the attachment for details.

Sincerely yours,

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors have successfully addressed all the comments provided by the reviewer. The quality of the paper, as well as its presentation, have been substantially improved. The reviewer has no major concerns regarding the manuscript. The authors should only check the references list, as many papers are wrongly cited, e.g., the first and the last name of the authors are stuck together, wrong years of publication, etc. The latter should be corrected before publication.

Author Response

Reviewer: #2

 

Comments：

 

The authors have successfully addressed all the comments provided by the reviewer. The quality of the paper, as well as its presentation, have been substantially improved. The reviewer has no major concerns regarding the manuscript. The authors should only check the references list, as many papers are wrongly cited, e.g., the first and the last name of the authors are stuck together, wrong years of publication, etc. The latter should be corrected before publication.

 

Response 2

 

The authors have successfully addressed all the comments provided by the reviewer. The quality of the paper, as well as its presentation, have been substantially improved. The reviewer has no major concerns regarding the manuscript. The authors should only check the references list, as many papers are wrongly cited, e.g., the first and the last name of the authors are stuck together, wrong years of publication, etc. The latter should be corrected before publication.

 

A: Thank you for your comment. We are so sorry that we made references errors although we revised the manuscript in this revision. We have re-searched the citation format of papers on the internet.

 

Finally, we are very thankful your comment to revise our manuscript. Thank you again for reviewing our paper. Your comments have considerably assisted us in improving the quality of our paper. I hope that our work this time is satisfactory.

Reviewer 3 Report

The authors have substantially improved the paper. They successfully addressed most of my comments and suggestions. However, there are some issues that need to be solved (I will analyze the responses provided by the authors for each of the issues I raised my previous review):

1. English language still needs some polishing. Please check the entire manuscript, not only the examples I give/gave. Some examples: a) in line 10 the sequence “To dispose the problem” must be changed into “To address the problem”; b) the sentence started in line 27 (“Compared…) is grammatically incorrect – I suggest “Compared with the traditional ad hoc network, the topology of the opportunistic networks changes dynamically and no relatively stable transmission path between nodes may be identified“; c) in line 44 there is the word “seasonable” which has nothing to do with the idea of the sentence; d) in line 126 there is “node. And” instead of “node and”; e) I suggest that the sentence started in line 148 and ended in line 150 (“Location: …”) to be changed into “The location is indicated by the two dimensional coordinates of node (xi, yi), while the velocity is specified by the current moving speed value of the node and the direction of node movement.”; f) the two consecutive sentences from lines 245-246 must be reshaped because are grammatically wrong; g) the sentence from line 266 must be reshaped.

2. Solved.

3. Solved.

4. I am not satisfied with the answer the authors provided. The paragraph started in line 157 and ended in line 164 is confusing. Also the reasons to assume Gaussian distribution are not convincing. In order to solve this issue, I suggest to replace this paragraph (except the last sentence that introduces eq.(2) that will be kept) with a simple sentence. “We assume that that the node mobility satisfies the Gaussian distribution”.

5. Solved.

6. Solved.

7. Solved.

8. Solved.

9. I am satisfied with the answer, but there is a mistake in Eq. (22): k must be replaced by N.

10. Solved.

11. Solved.

12. Solved.

13. I am satisfied with the answer, but to be grammatically correct, the sentences from lines 380-381 must be replaced by “The change law of average end-to-end delay with simulation time length is introduced and the effect of the number of nodes on the average end-to-end delay is studied.“

14. It is important for the reader to know that your method can be also successfully applied to other networks. IN order to solve this issue, please insert the following sentence just after line 164: “The presented method may be successfully used for vehicular ad hoc networks (VANETs) [(“A tutorial survey on vehicular ad hoc networks” DOI: 10.1109/MCOM.2008.4539481], or wireless sensor, actuator and robot networks (WSARNs) [“Towards wireless sensor, actuator and robot networks” doi:10.1016/j.jnca.2016.01.013)]”.

15. Solved.

Author Response

Dear reviewers and editor,

We are very grateful to the reviewers and the editor of the paper for their critical reading of the manuscript and their valuable suggestions for the paper’s further improvement.

We have checked the manuscript and revised it according to the comments. The following content is a point-to-point response to the reviewers’ comments.

 See the annex for details.

Sincerely yours,

Author Response File: Author Response.pdf

Round 3

Reviewer 3 Report

The authors have successfully addressed my comments.