3MSF: A Multi-Modal Adaptation of the 6TiSCH Minimal Scheduling Function for the Industrial IoT

Round 1

Reviewer 1 Report

The authors of this work devised the Multi-Modal Minimal Scheduling Function (3MSF) for the TSCH link layer, combining the ideas gathered from earlier work on the routing layer, resulting in a 6TiSCH architecture able to dynamically exploit modern multi-modal hardware on a per-link basis through variable timeslot duration, simultaneous transmission, and routing metric normalization. The work is very interesting and the results will benefit a large audience. However, some revisions are required before further processing.

1. The related work section requires a moderate expansion. A few more related works should be added and discussed accordingly.

2. In Figure 5. Example of the slotframe structure of the Multi-Modal Minimal Scheduling Function (3MSF). As 3MSF is a distributed scheduler, the contents of the slot frames shown constitute the schedule as seen by a single node (i.e., #2) in a small example network, the authors revise the texts at the bottom upwards. I think a 180-degree clockwise turn will be fine.

3. The authors should avoid the use of short forms like can't. See line 396 for example: With MSF, a node can’t use an autonomous Tx cell towards a neighbor to which it...

4. The key results need to be compared with related works in the literature.

5. I think the discussion could be expanded and the conclusion should be separated from the discussions.

6. A few more recent reference materials could be added and discussed briefly.

Minor English editing is required.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The authors designed a multimodal minimum planning function (3MSF), which is partially based on: a solution from the literature. They described its design in great detail and discussed the rationale for each choice made. Subsequently, in order to demonstrate the functionality and flexibility of the proposed solution, they evaluated three basic scenarios by simulation. The subject covered is very interesting and the contribution of this work is well presented, however a few remarks must be made to improve the quality of the article:

- Please improve the summary in order to properly describe the paper.

- Add a paragraph that clearly describes the contribution of the paper.

- The diagrams in Figures 8, 12 and 13 require more refinement.

- Add the conclusion section to the paper.

Thank you again for your contribution.

Minor editing of English language required

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

1.In the article scheduling for industrial IoT as a multi-modal adaptation of the 6TiSCH minimal scheduling function (3MSF) is examined. Note multi-hop networks are under consideration as well. 

2.The authors designed the Multi-Modal Minimal Scheduling Function (3MSF), which is based on three components: (a) the 6TiSCH Minimal Scheduling Function (MSF); (b) a state-of-the-art solution (from literature); and (c) design considerations for a multi-modal 6TiSCH architecture (from the authors work). 

3.The discussion of the rationale behind every choice made is presented. 

4.Three basic scenarios are evaluated: (i) through simulation, (ii) through showcasing both the functionality, and (iii) through flexibility of the 6TiSCH implementation. 

5.In general the article is prepared at a very good level (all parts: introduction, description of the considered engineering problem, the authors approach, simulation results and discussion, conclusion, the pointed out future research directions, reference list).  The illustrative materials are useful. 

6.It may be useful to present information on relative works in a structured form (e.g., as a table and/or as a taxonomy/framework).

7.It is necessary to improve the presentation quality of figures 9, 10, 11.

8.It may be important to present the optimization scheduling model, i.e., variables, objective function(s), constraints (including the description of the model type and its complexity).

9.In general the article materials are important for the existing communication systems and for the future communications. The article material can be extended to prepare a useful tutorial.

10.The article can be accepted (after minor revision).

Author Response

Please see the attachment.

Author Response File: Author Response.pdf