Performance Evaluation and Comparison of Cooperative Frameworks for IoT-Based VDTN

Round 1

Reviewer 1 Report

This paper describes the VDTNS technology based on the Internet of Things and six different node cooperation technologies, and through a large number of simulations, evaluates the impact of six different cooperation technologies on network performance from different aspects such as packet transmission probability, packet transmission delay, throughput, overhead ratio, throughput, packet loss, energy consumption, and puts forward targeted suggestions. The logic of this paper needs to be polished. Moreover, the writing of the paper needs more improvement.

In Section 3, some formulas should be added to explain the last four collaboration technologies.

In Section 4.2, one sentence is repeated twice: "Figure 2 shows the results obtained for packet delivery delay for all six IoT-Based VDTN schemes namely SOS, HBDS, CTMS, RDMEG, IPS, and ATVDC".

In Section 4.2, ATVDC sends data packets 30 minutes, 17 minutes, 16 minutes, 20 minutes and 22 minutes, it is faster than SOS, HBDS, CTMS, RDMEG and IPS respectively, but it is not reflected in the result figure and result table.

Figure 6 should be put at the end of Section 4, not at the end of Section 5.

Author Response

Dear Editor,

Please find the attached document.

Regards,

Dr. Ghani Ur Rehman

Author Response File: Author Response.docx

Reviewer 2 Report

The authors conducting a comparative study for different  strategies for cooperation in IoT-Based VDTNs namely:

SOS, HBDS, CTMS, RDMEG, IPS, ATVDC.

Though there is no new scheme presented, yet the study can help having a glimpse of the performance for different VTDN Cooperation Strategies. 

I notice the redundancy in the data presentation. For example:

Table 3 is the same as Figure 1, Table 4 and Figure 2, ........Table 8 and Figure 6. There is no need to present the data twice.

I would urge the authors to invoke statistics in their simulation, by showing averages of multiple runs. This will add more credibility to this work. Adding simulation shots from the network simulator (NS2), would be more valuable than adding redundant tables or figures.

Author Response

Dear Editor,

Please find the attached document.

Regards,

Dr. Ghani Ur Rehman

Author Response File: Author Response.docx

Reviewer 3 Report

This paper evaluates the performance of several cooperative strategies for IoT-based VDTN. Below is some comments on the paper:

- Six cooperation strategies to be compared are not proposed by the authors. It needs to make it clear that this paper evaluates the performance of existing cooperation strategies. 

- Is there any criteria in choosing the six strategies? 

- In Section 3, it will be better if we can see a figure or illustration on the how the IoT-based VDTN looks like. 

- In Section 4, there is too much description on ns-2. Maybe you can just refer other source for detailed information. Instead, it will be better to describe experiment settings like vehicle mobility model, data arrival processes etc. 

- Is there any description on the mobility model? 

- In page 8, line number 298 says that the SOS performs best, but there is no description on why. When explaining the figure, it will be better to explain the results rather than commenting the values. 

Author Response

Dear Editor,

Please find the attached document.

Regards,

Dr. Ghani Ur Rehman

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I have no more comments for this paper.

Author Response

Thanks

Author Response File: Author Response.docx

Reviewer 2 Report

The authors has performed the modifications mentioned in round 1. I am satisfied with their current version.

Author Response

Thanks

Author Response File: Author Response.docx

Reviewer 3 Report

All the issues in the previous round of review are well addressed. 

Author Response

Thanks

Author Response File: Author Response.docx