Multi-Controller Deployment in SDN-Enabled 6G Space–Air–Ground Integrated Network

Round 1

Reviewer 1 Report

The article is technically sound and provides an interesting and novel solution. It is well motivated within the framework of 6G and SAGIN, although the later on the article is completely focused on other physical/geometrical problems. For instance SDN technology is basically introduced in the title and motivation but no further comments about SDN (implementations, restrictions, implications) are done. Just the 'SDN controller' is mentioned here and there.

Beyond that the deployment proposal and the experimentation is fine, and interesting.

However, the article requires a strong review due to a lot of English mispelling problems, and a lot of mistakes. It is impossible to list them all here in the review. Just as examples:

• sometimes n-k-means, sometimes N-k-means
• no usage of ',' to separate big numbers
• when using the '(' after a work, normally no whitespace is left
• internet instead of Internet
• random usage of capitalization (eg. pag3, line 51 ,Network, page 4 like 58 North... but not south, etc.), page 5 like 141, 'problem formulation'... in a title
• random use of contractions: doesn't (will during most of the text no contractions are used)
• You should use et al.   (colon after al)
• You should use etc. (colon after etc)
• '...', just 3 points
• in section 3.2, S and C are from 1 to m while you mention that the maximum for them both is n (and later for E it is not clear which one gows until n or m).
• page 7, line 182 'ms unit'
• 'earth' should be capitalized (for the planet)
• page 8 line 200: condition Three, while 1, 2 and 4

It looks like different authors wrote the document with many different styles and eventually some parts look like translated using an automatic translator: page 11 paragraph starting on line 262, first paragraph of the conclusion...

Please review the whole article possibly with a native speaker because it really requires a lot of work there and the scientific work is in fact interesting.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The paper is well written and the methodology is described property. The usage of hierarchical distribution of SDN controllers has been researched several times with different algorithms. Nevertheless, the application of hierarchical distribution of SDN controllers to different layers of satelites is quite interesting.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf