TLS-VaD: A New Tool for Developing Centralized Link-Scheduling Algorithms on the IEEE802.15.4e TSCH Network

Round 1

Reviewer 1 Report

The authors present a software program that explicitly translates scheduling policies for IEEE802.15.4e networks and generates channel occupancy patterns. The authors refer to this task as a simulation and cite some simulators such as NS, Opnet and Omnet as other reference simulators. This is questionable, since what by using such simulators can be done is to reproduce and analyze networking scenarios numerically since such scenarios are so complex that cannot to be analyzed mathematically. In this regard, the software implemented, as far as appears in the paper, seems to implement so existing combinatorial algorithms. This task is different from what is generally regarded as a network simulator. For example, the typical description a simulator tailored to a specific environment, the structure of which can be used as a reference to restructure the description of the tool, can found in https://doi.org/10.1016/j.nancom.2011.09.002

Having said this, which translates into the need of rewriting in particular the objectives of the paper and the description of the experimental results, the technical work is appreciable. The implemented tool, which is suggested to be referred to as a design tool, or a research support tool, seems to be quite well implemented and worth of description.

For what concerns the background description, it is well done, since the reader has to know the technical details of IEEE802.15.4e TSCH in order to understand the presented case studies.

An aspect that is not sufficiently described is the implementation of the tool. How was it written? Have any specific libraries and design patterns been used? Have the visualization tools been implemented from scratch or imported?

The authors are encouraged to deeply revise the structure of the paper.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The main theme of the paper is to introduce the TSCH link scheduling simulator. However, it spends more than half of the volume in background description. Though it is informative, it can be made more concise. For the simulator itself, section 5 is also too long. It does not give much technical information. At best it is like the user manual on the simulator. Section 5.2 on simulator validation is trivial and can be deleted.

 

There are some strong assumptions in this study that connectivity and queue information is passed between each node and the master node before schedule can be calculated and then resulting schedule needs to be sent back to each node. How these are done before the schedule is calculated? It sounds like a chicken-and-egg problem.

 

FTSA and FLSA are two scheduling algorithms that are compared with the IRByTSA. However, the authors did not provide references on who proposed FTSA and FLSA. Or are these two algorithms also proposed by the authors? IRByTSA actually is not too different from FTSA and FLSA. Why using these two for comparison?

If FTSA and FLSA are other’s idea, then it is hard to claim much innovative credit on proposing IRByTSA. The performance test in section 6 also shows that IRByTSA is better than FLSA in slots used but worse than FLSA in cycle number. Therefore, it is hard to say that IRByTSA provides better performance than FLSA.

 

There are some errors/weakness that should be corrected/improved:

In the Maximal match pseudo code, line 2, “While (no more edges can be added)” does seem to be correct. In equation (4), both ts_i(s) and q_i(s) are not defined. In Table 2, both ND and i refer to “number of nodes”. In Figure 19, both “For” statements are not consistent with text descriptions.

Author Response

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Reviewer 3 Report

In the upcoming 5G era, a large part of the IOT networks will be built based on the protocol IEEE 802.15.4. This paper summarizes the work on TLS Simulator: A New Tool for Developing
Centralized Link-Scheduling Algorithms. The work is interested and valid.    TLS is not a common acronym. TSCH is not also. More tables or bullet lists to summarize the key features and distinguishable algorithm procedures.     Shorten the page of this article. Some screen snapshots of this software can be replaced by the refines sentences and more official graphs.    More comparison with the reference simulators is needed. The reference work on the physical layer network simulator can also be briefly summarized. For example,   *J.D. Beshay, K.S. Subramani, N. Mahabeleshwar, E. Nourbakhsh, B. McMillin, B. Banerjee, R. Prakash, Y. Du, P. Huang, T. Xi, Y. You, J.D. Camp, P. Gui, D. Rajan, J. Chen,
Wireless Networking Testbed and Emulator (WiNeTestEr), Computer Communications, Volume 73, Part A, 2016, Pages 99-107, ISSN 0140-3664,   *P. Huang, Y. Du and Y. Li, "Stability Analysis and Hardware Resource Optimization in Channel Emulator Design," in IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 63, no. 7, pp. 1089-1100, July 2016.   *P. Huang, "A Novel Structure for Rayleigh Channel Generation With Consideration of the Implementation in FPGA," in IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 63, no. 2, pp. 216-220, Feb. 2016.   Some evaluations on different algorithms are recommended.     

Author Response

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Round 2

Reviewer 1 Report

The paper has been improved in comparison with the first review round. In particular the work done on section 5 is appreciated. Even the objective description has been improved. For this reason the paper is considered sufficiently mature for being accepted.

Reviewer 3 Report

The authors fixed my comments.