Towards Collaborative and Dynamic Spectrum Sharing via Interpretation of Spectrum Access Policies
Round 1
Reviewer 1 Report
A policy-based access control system for cognitive radio is proposed in this article.
The presentation is of high level of abstraction, and there can be a gap to practicers.
A number of policy -based approaches are listed, but not differentiated, in Section 2. The motivation of the proposed becomes difficult to identified.
The adequacy of employing ontology in the design of the proposed system demand further justification.
Examples on the concerned issues, spectrum sharing, should be given in the presentation of the proposed policies in Section 5.
The paper had demonstrated the feasibility of the proposed approach. However, lacking comparative study renders the work less persuasive.
Author Response
Reviewer 1:
A policy-based access control system for cognitive radio is proposed in this article.
The presentation is of high level of abstraction, and there can be a gap to practicers.
A number of policy-based approaches are listed, but not differentiated, in Section 2. The motivation of the proposed becomes difficult to identified.
Answer 1: Following the recommendations of this reviewer, we extended the descriptions of the various types or radio and provided more explanation of the policy-based approach in Section 1.
The adequacy of employing ontology in the design of the proposed system demand further justification.
Answer 2: Trying to satisfy the request of this reviewer, we made modifications to Section 1 and Section 2 of the paper. In particular, at the end of Section 2, we provided more explanation on why ontologies are needed, or in other words, why other (static policy) approaches do not work too well. While doing this, we tried to make things more precise and convincing, while keeping the size of the paper under control. We certainly hope that this reviewer will find our modifications sufficient.
Additionally, we have expanded Section 5. We provided a figure that gives a view of a small fragment of an ontology and explained the meaning of symbols in the figure. We also indicated how an ontology is encoded using the RDF triples.
Examples on the concerned issues, spectrum sharing, should be given in the presentation of the proposed policies in Section 5.
Answer 3: We tried to introduce the notion of policy in a progressive way. Towards this aim, we expanded the description of Cognitive Policy Based Radio (CBPR) in Section 2. Then, in the same section, we provided some explanation of the role policies play in CPBR. Then, in Section 5, we show an example of a policy expressed in SPARQL. Although policies in our system are not expressed in SPARQL, SPARQL is more succinct than the OWL RL rules, so it seems justifiable to use it as a front-end language.
The paper had demonstrated the feasibility of the proposed approach. However, lacking comparative study renders the work less persuasive.
Answer 4: We have extended Section 7 – discussion. We reviewed the most relevant papers that address similar issues as our paper. This is as far as we could go since the papers don’t have a common frame – a base of policies and scenarios.
Reviewer 2 Report
I find the article as a nice read, an interesting contribution for the development of collaborative spectrum sharing systems. The authors discuss the problem of spectrum sharing among the radios within the same group, and try to offer their own suggestions for a policy-based solution.
The paper has a logical course, with a two-step introduction (section 1 and 2) where the authors present the definitions of cognitive radio, a number of capabilities need to be supported by a radio, the context for cognitive radio and the policy based cognitive radio; after that, in the 3rd section they describe the Cognitive Engine, the extended OODA loop and the architecture of the experimental system CRE.
In the 4rd section, they present the language (ontologies) in which to represent the messages for the implementation of communication systems, while in the 5th section, the authors discuss the two kinds of policies for the present study.
In the 6th section the authors detail the way they implemented the architecture of their experimental system, going through policy interpretation, policy for transmission opportunities, policy-based definition of rendezvous, policy-based optimization of knobs. In the end of the paper, they evaluate the concerns of missing some of the facilities they mention in their study.
Based on the Turnitin software (see the attached .pdf file), some pieces of the theoretical parts appear to have been copy-pasted (without proper quotation marks or modification) from the cited references. I would suggest the authors (so as not to have problems in their future career) to try to reproduce using their own words these elements of theory, and where it is not possible to put them in quotes “ “. There are paragraphs that I strongly suggest should be at least slightly modified or put in quotation marks so to avoid them to appear so obvious in Turnitin or other plagiarism software: paragraphs-rows 15-21, 59-69, 71-81, 442-459, 611-615
I would recommend to the authors a further reading by a native English speaker, or at least a very careful reading, because there are some errors to be corrected, for example, in the title of the second section there is the misspelled word “Cogntivie” (perhaps should be Cognitive).
I would also advise the authors to correctly explain the acronyms, the first time they use them. For example, they use “RF environment” on the first page, perhaps they should explain in the parenthesis Radio Frequency (RF). The same thing with Application Programming Interface (API) etc.
I appreciate the article as an interesting working study, with some state of art technologies applied, addressing some pertinent necessitates in the field, backed up by an important national grant, with a few things to improve for publication in this journal.
Comments for author File: 
Comments.pdf
Author Response
Reviewer 2:
I find the article as a nice read, an interesting contribution for the development of collaborative spectrum sharing systems. The authors discuss the problem of spectrum sharing among the radios within the same group, and try to offer their own suggestions for a policy-based solution.
The paper has a logical course, with a two-step introduction (section 1 and 2) where the authors present the definitions of cognitive radio, a number of capabilities need to be supported by a radio, the context for cognitive radio and the policy based cognitive radio; after that, in the 3rd section they describe the Cognitive Engine, the extended OODA loop and the architecture of the experimental system CRE.
In the 4rd section, they present the language (ontologies) in which to represent the messages for the implementation of communication systems, while in the 5th section, the authors discuss the two kinds of policies for the present study.
In the 6th section the authors detail the way they implemented the architecture of their experimental system, going through policy interpretation, policy for transmission opportunities, policy-based definition of rendezvous, policy-based optimization of knobs. In the end of the paper, they evaluate the concerns of missing some of the facilities they mention in their study.
Based on the Turnitin software (see the attached .pdf file), some pieces of the theoretical parts appear to have been copy-pasted (without proper quotation marks or modification) from the cited references. I would suggest the authors (so as not to have problems in their future career) to try to reproduce using their own words these elements of theory, and where it is not possible to put them in quotes “ “. There are paragraphs that I strongly suggest should be at least slightly modified or put in quotation marks so to avoid them to appear so obvious in Turnitin or other plagiarism software: paragraphs-rows 15-21, 59-69, 71-81, 442-459, 611-615
I would recommend to the authors a further reading by a native English speaker, or at least a very careful reading, because there are some errors to be corrected, for example, in the title of the second section there is the misspelled word “Cogntivie” (perhaps should be Cognitive).
I would also advise the authors to correctly explain the acronyms, the first time they use them. For example, they use “RF environment” on the first page, perhaps they should explain in the parenthesis Radio Frequency (RF). The same thing with Application Programming Interface (API) etc.
Answer 1: Although we tried to make it clear where the phrases came from, we agree with this reviewer that this should be made more explicit. Following the advice of this reviewer, we added quotation marks in many places in the paper. In other places we reformulated some phrases to show that the phrases were not just copy/pasted from other documents. The most difficult for us is to modify the phrases that we formulated in other papers that we have published; we tried to fix this problem the best we could. We hope that the modifications to some of the sentences have improved the English.
We were not sure about the issue with lines 611-615. Perhaps this was referring to Figure 9? While this figure looks like many others that can be found on the Internet, this figure was the result of our Matlab simulations. Hopefully this clarifies the issue with these lines.
I appreciate the article as an interesting working study, with some state of art technologies applied, addressing some pertinent necessitates in the field, backed up by an important national grant, with a few things to improve for publication in this journal.
Answer 2: We greatly appreciate this reviewer’s good words about our work.
Round 2
Reviewer 1 Report
Issues in version 1 are addressed.
Quality of illustrations need to be improved.
Author Response
We regenerated some of the figures and also increased the sizes. The text has been edited with the intent of addressing the concerns of this reviewer. Since in some cases large portions of the text were highlighted, it was difficult to pinpoint exactly the reviewer's concerns, but we tried to do our best. We certainly hope the current version is to the satisfaction of this reviewer.
