Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript presents a comprehensive and technically thorough analysis of traffic protection schemes in advanced WDM-PONs, supported by an extensive evaluation framework and a significant amount of detailed results. The integration of optical power budget considerations into the assessment is certainly relevant and adds practical value to the study, particularly in terms of aligning performance evaluation with realistic deployment constraints. However, the claimed novelty of this aspect appears to be somewhat overstated, as such considerations are generally expected and inherently associated with rigorous analyses of optical access networks. Compared with the previous study by the same authors in Applied Sciences, the paper shows a different analytical dimension from the optical layer point of view, formulating explicit power‑budget and link‑margin equations, assembling component‑level loss models (fiber, connectors, splices, splitters/AWGs, MUX/DEMUX, circulators), and delivering a dedicated WDM‑PON Network Power Budget Evaluator that determines technical realizability in P2MP, ring, and combined metro‑access architectures. As a result, Photonics reports novel feasibility outcomes thereby complementing and constraining the earlier economic conclusions by showing when cost‑effective designs cannot be deployed without violating optical budgets. Photonics advances the line of work from economic viability to physical‑layer viability, adds a new simulation tool and quantitative datasets at the component level, and delivers first‑time power‑budget–driven guidance for selecting protection schemes in WDM‑PON planning.

The manuscript is written in a clear, rigorous, and scientifically appropriate style, and a coherent narrative throughout. Its overall structure is well organized. The text is free of typographical or grammatical errors, and the figures are consistently well designed, properly labelled, and correctly referenced within the manuscript. Likewise, the bibliographic sources are relevant, up‑to‑date, and technically meaningful for the field, and the reference list is carefully formatted, comprehensive, and methodically ordered.

Below, the reviewer provides several technical comments and suggestions for the authors’ consideration:

• The authors have restricted their analysis to the spectral region of the third optical transmission window, where attenuation levels are relatively low and performance margins are generally more favourable. However, standardized PON systems defined in ITU‑T specify that the upstream transmission channel, from the user toward the central office, is conventionally allocated to the second optical window, Recommendations: G.984 / GPON (1310 nm), G.987 / XG-PON (1270 nm), G.9807 / XGS-PON (1270 nm), or EPON (IEEE 802.3ah at 1310 nm). This is a band characterized by significantly higher propagation losses than those considered in the present study. This discrepancy has important implications: relying exclusively on third‑window parameters may lead to an overestimation of available power margins and, consequently, an optimistic assessment of link feasibility, especially in scenarios involving long distribution fibers, protection schemes with duplicated paths, or architectures already operating near their budget limits.

In particular, the channels transmitted within these wavelengths experience significantly greater degradation when traversing longer distances, especially when traffic must be rerouted through sub‑optimal or extended alternative paths to restore service in the presence of failures. This increased attenuation further exacerbates the upstream power budget limitations discussed previously and may critically reduce the feasibility margins of protection schemes that depend on non‑ideal rerouting.

For a complete and methodologically rigorous evaluation, I strongly encourage the authors to revisit and reformulate their analysis by incorporating the second‑window attenuation regime, ensuring that upstream constraints are properly represented and that the resulting conclusions accurately reflect the operational realities of standardized PON deployments.

• In line 274, the authors state that “The receiver’s sensitivity establishes the minimum optical power required”. It is important to note that receiver sensitivity is intrinsically linked to specific quality‑of‑service thresholds, typically defined in terms of bit‑error rate (BER), Q‑factor, or signal‑to‑noise ratio (SNR), all of which determine the operational reliability of the optical link. In its current form, the manuscript does not explicitly specify the target BER or corresponding performance criteria used as the basis for the sensitivity values adopted in the power‑budget calculations.

I strongly recommend that the authors clarify the BER (or equivalent metric) assumed in their analysis and incorporate this information explicitly into the text to ensure technical completeness.

 

• In line 293, the authors present the “distribution loss for splitters” and provide a table containing the theoretical splitting losses. Although they later acknowledge that the insertion loss is higher than the theoretical attenuation value due to additional interfaces (e.g., connectors), the explanation remains incomplete from an optical‑engineering standpoint. As is well established, the insertion loss of any splitter is inherently greater than the ideal distribution loss, because it includes not only the theoretical power‑division component but also the excess loss arising from fabrication tolerances, waveguide imperfections, internal scattering, and packaging. Therefore, for any practical input–output port configuration, a splitter must be characterized by its insertion loss, which is the sum of distribution loss + excess loss, rather than by the theoretical split loss alone. I would recommend that the authors revise this section to clarify this distinction explicitly, ensuring that the loss model used in the power‑budget calculations accurately reflects the real behavior of commercially available splitters and avoids underestimating the total attenuation introduced by these components.

 

The authors have presented an interesting and detailed study that offers practical value for the design of PON architectures incorporating protection mechanisms and traffic‑restoration strategies. However, in opinion of this reviewer, several important considerations should still be addressed before the manuscript can be deemed suitable for publication. Once the aforementioned issues have been addressed, the manuscript will be suitable for publication in Photonics.

Author Response

the Review Report (Reviewer 1)

The manuscript presents a comprehensive and technically thorough analysis of traffic protection schemes in advanced WDM-PONs, supported by an extensive evaluation framework and a significant amount of detailed results. The integration of optical power budget considerations into the assessment is certainly relevant and adds practical value to the study, particularly in terms of aligning performance evaluation with realistic deployment constraints. However, the claimed novelty of this aspect appears to be somewhat overstated, as such considerations are generally expected and inherently associated with rigorous analyses of optical access networks. Compared with the previous study by the same authors in Applied Sciences, the paper shows a different analytical dimension from the optical layer point of view, formulating explicit power‑budget and link‑margin equations, assembling component‑level loss models (fiber, connectors, splices, splitters/AWGs, MUX/DEMUX, circulators), and delivering a dedicated WDM‑PON Network Power Budget Evaluator that determines technical realizability in P2MP, ring, and combined metro‑access architectures. As a result, Photonics reports novel feasibility outcomes thereby complementing and constraining the earlier economic conclusions by showing when cost‑effective designs cannot be deployed without violating optical budgets. Photonics advances the line of work from economic viability to physical‑layer viability, adds a new simulation tool and quantitative datasets at the component level, and delivers first‑time power‑budget–driven guidance for selecting protection schemes in WDM‑PON planning.

The manuscript is written in a clear, rigorous, and scientifically appropriate style, and a coherent narrative throughout. Its overall structure is well organized. The text is free of typographical or grammatical errors, and the figures are consistently well designed, properly labelled, and correctly referenced within the manuscript. Likewise, the bibliographic sources are relevant, up‑to‑date, and technically meaningful for the field, and the reference list is carefully formatted, comprehensive, and methodically ordered.

We appreciate the Reviewer’s opinion, comments, and remarks. Detailed responses are provided below. Changes made in the revised manuscript are highlighted (a blue color). We would like to thank the respected Reviewer for his comments and remarks that make this paper better.

Below, the reviewer provides several technical comments and suggestions for the authors’ consideration:

• The authors have restricted their analysis to the spectral region of the third optical transmission window, where attenuation levels are relatively low and performance margins are generally more favourable. However, standardized PON systems defined in ITU‑T specify that the upstream transmission channel, from the user toward the central office, is conventionally allocated to the second optical window, Recommendations: G.984 / GPON (1310 nm), G.987 / XG-PON (1270 nm), G.9807 / XGS-PON (1270 nm), or EPON (IEEE 802.3ah at 1310 nm). This is a band characterized by significantly higher propagation losses than those considered in the present study. This discrepancy has important implications: relying exclusively on third‑window parameters may lead to an overestimation of available power margins and, consequently, an optimistic assessment of link feasibility, especially in scenarios involving long distribution fibers, protection schemes with duplicated paths, or architectures already operating near their budget limits.
• Response: The comment is accepted; Section 4 "WDM-PON Components and their Power Budget Parameters" is markedly expanded. In new rows, significant reflections on optical power budget calculation in downstream and upstream directions of the signal transmission in different optical transmission windows are emphasized. Simultaneously, feasibility margins are discussed in both directions.

In particular, the channels transmitted within these wavelengths experience significantly greater degradation when traversing longer distances, especially when traffic must be rerouted through sub‑optimal or extended alternative paths to restore service in the presence of failures. This increased attenuation further exacerbates the upstream power budget limitations discussed previously and may critically reduce the feasibility margins of protection schemes that depend on non‑ideal rerouting.

For a complete and methodologically rigorous evaluation, I strongly encourage the authors to revisit and reformulate their analysis by incorporating the second‑window attenuation regime, ensuring that upstream constraints are properly represented and that the resulting conclusions accurately reflect the operational realities of standardized PON deployments.

• Response: The comment is accepted; Section 6 "The WDM-PON Network Power Budget Evaluator" is expanded with the precising that the total path attenuation of the WDM-PON optical link is computed for the downstream direction. Also, Section 7 "Evaluation of WDM-PON Traffic Protection Schemes" is arranged and extended with explanations of the optical power budget calculation for various directions of the signal transmission depending on architecture of the WDM-PON traffic protection schemes.

• In line 274, the authors state that “The receiver’s sensitivity establishes the minimum optical power required”. It is important to note that receiver sensitivity is intrinsically linked to specific quality‑of‑service thresholds, typically defined in terms of bit‑error rate (BER), Q‑factor, or signal‑to‑noise ratio (SNR), all of which determine the operational reliability of the optical link. In its current form, the manuscript does not explicitly specify the target BER or corresponding performance criteria used as the basis for the sensitivity values adopted in the power‑budget calculations.

I strongly recommend that the authors clarify the BER (or equivalent metric) assumed in their analysis and incorporate this information explicitly into the text to ensure technical completeness.

• Response: The comment is accepted; Subsection 4.2 "Optical receivers" is expanded with the specification of the target BER, data rate and line code used as the basis for the sensitivity values adopted un the power budget calculations to ensure technical completeness.

• In line 293, the authors present the “distribution loss for splitters” and provide a table containing the theoretical splitting losses. Although they later acknowledge that the insertion loss is higher than the theoretical attenuation value due to additional interfaces (e.g., connectors), the explanation remains incomplete from an optical‑engineering standpoint. As is well established, the insertion loss of any splitter is inherently greater than the ideal distribution loss, because it includes not only the theoretical power‑division component but also the excess loss arising from fabrication tolerances, waveguide imperfections, internal scattering, and packaging. Therefore, for any practical input–output port configuration, a splitter must be characterized by its insertion loss, which is the sum of distribution loss + excess loss, rather than by the theoretical split loss alone. I would recommend that the authors revise this section to clarify this distinction explicitly, ensuring that the loss model used in the power‑budget calculations accurately reflects the real behavior of commercially available splitters and avoids underestimating the total attenuation introduced by these components.

• Response: The comment is accepted; Subsections 4.3 "Remote nodes" and 4.4 "Other relevant components" are expanded with explanations how values of insertion losses for power splitters, AWG devices and other passive optical components were selected. Selected values from the commercial catalog accurately reflect the real behavior of commercially available components and they are simultaneously complementing with standard values for the insertion loss parameters to justify the worst case for each passive optical component. By this way, the loss model used in the power budget calculations ensures that the total attenuation introduced by these components avoids underestimating. Within this context, a list of appropriate references is markedly enhanced.

The authors have presented an interesting and detailed study that offers practical value for the design of PON architectures incorporating protection mechanisms and traffic‑restoration strategies. However, in opinion of this reviewer, several important considerations should still be addressed before the manuscript can be deemed suitable for publication. Once the aforementioned issues have been addressed, the manuscript will be suitable for publication in Photonics.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The aim of this paper is to develop and show a simulation-based optical power budget analysis framework for potential WDM-PON traffic protection schemes implemented as a tailored Excel/VBA tool‚ and conduct a more thorough analysis of the various types of P2MP‚ ring access and metro-access topology under specific protection schemes and assess which topologies remain physically feasible under realistic passive component parameters and standard power budget parameters․

 

Self-citation transparency: A paragraph should be added to distinguish the technical novelty of this submission from [16]‚ [18]‚ [19]‚ [20] and elaborate on the overlap in scope and methodology․

Novelty statement: Section 3 must be rewritten as a self-contained technical section rather than a collection of pointers to prior work; sufficient background must be reproduced within this manuscript

I would appreciate if the authors could compare their experimental results with other state-of-the-art contributions outside their group‚ such as (doi: 10․1364/JOCN․391830, 10․1109/JLT․2016․2637825, 10․3390/electronics9071081)‚ to further clarify their position in the field of research․

Sensitivity analysis: Add a parametric study of how feasibility margins vary with fiber attenuation‚ number of connectors‚ transmitter power‚ and splice loss to reflect what has been observed in the field․

Considering the margin of feasibility‚ Tables 7 and 8 are extended to specific comfortably feasible‚ marginally feasible and infeasible cases․ +0․30 dB cannot be interpreted with the same certainty as +10 dB․

Essentially: metro-access: rather than simply closing on the cardinality limits I see‚ I would like to frame these discussion in terms of concrete engineering trade-offs: where to place amplifiers effectively‚ how many of them‚ and/or reducing reach․

Component parameter sourcing: complement the commercial vendor catalog (reference [26]) with literature or standard values for the insertion loss parameters and justify the worst case parameters chosen vs․ ITU-T recommendations

Benchmark: numerical cross-validation of the formula results from the Excel/VBA tool against an independent analytical calculation or a published reference scenario should be performed to show computational correctness

 

Few new contributions to science have been created relative to the author's previous work‚ and self-citation of the reference list is close to 40%․ The core of the paper is in [18] and [19]․ The power budget formulas are standard textbook formulas‚ and the calculations do not appear to have been analytically developed․ In addition‚ the Excel/VBA implementation does not represent a methodological advance over optical link budget packages․ The lack of sensitivity analysis affects the generalizability of the findings․

 

The paper closes the gap between practically relevant resilience in traffic protection and the optimal optical physical-layer feasibility of bi-directional WDM-PON networks․ The systematic assessment of eight protection variants across three groups of WDM-PON topologies in an interactive simulation tool creates a benchmark for practitioners and researchers in the field․ The paper is generally well organized and clearly written․

 

Although some issues are dealt with in the manuscript‚ it does not reach the expected level of very high impact factor journal mostly due to a lack of novelty‚ a high percentage of self-citations‚ and the lack of a sensitivity analysis․ The major revision should address the points mentioned above‚ namely‚ the technical differentiation with respect to other works (particularly reference [18])‚ the references‚ decoupling the entire Section 3 and the parametric sensitivity analysis․ If revised as suggested‚ this manuscript should act as a useful contribution to the planning of optical access networks․

Author Response

the Review Report (Reviewer 2)

The aim of this paper is to develop and show a simulation-based optical power budget analysis framework for potential WDM-PON traffic protection schemes implemented as a tailored Excel/VBA tool‚ and conduct a more thorough analysis of the various types of P2MP‚ ring access and metro-access topology under specific protection schemes and assess which topologies remain physically feasible under realistic passive component parameters and standard power budget parameters․

We appreciate the Reviewer’s opinion, comments, and remarks. Detailed responses are provided below. Changes made in the revised manuscript are highlighted (a blue color). We would like to thank the respected Reviewer for his comments and remarks that make this paper better.

Self-citation transparency: A paragraph should be added to distinguish the technical novelty of this submission from [16]‚ [18]‚ [19]‚ [20] and elaborate on the overlap in scope and methodology․

Response: The comment is accepted; Section 1 "Introduction" is markedly expanded (Rows 128-135). Here, the common base of our research activities is presented together with the novelty of this submission for explaining the overlap in scope. Following paragraphs introduce main contributions of previous submissions in more detail. Also, Section 2 "Materials and Methods" is arranged, where the methodology is involved.

Novelty statement: Section 3 must be rewritten as a self-contained technical section rather than a collection of pointers to prior work; sufficient background must be reproduced within this manuscript.

Response: We appreciate the Reviewer’s comments. Section 3 "Presumptive WDM-PON Architectures" with a set of traffic protection schemes is necessary for fully understanding of different realized performance analyses. These protection schemes considered for presumptive WDM-PON architectures create an inevitable component of their real implementations and they are completely involved in the presented simulation tool for analyzing optical power budget of various potential traffic protection schemes.

I would appreciate if the authors could compare their experimental results with other state-of-the-art contributions outside their group‚ such as (doi: 10․1364/JOCN․391830, 10․1109/JLT․2016․2637825, 10․3390/electronics9071081)‚ to further clarify their position in the field of research․

Response: The comment is accepted; Section 1 "Introduction" is markedly expanded (Rows 104-114, 126-127). Here, other state-of-the-art contributions outside our group together with relevant standards are compared to further clarify their position in the field of research. Within this context, a list of appropriate references is markedly enhanced.

 

Sensitivity analysis: Add a parametric study of how feasibility margins vary with fiber attenuation‚ number of connectors‚ transmitter power‚ and splice loss to reflect what has been observed in the field․

Response: The comment is accepted; Section 5 "Power Budget Calculation of the WDM-PON Optical Link" is arranged, where the total path attenuation varied with fiber attenuation‚ number of connectors‚ transmitter power‚ and splice loss is involved. Also, Section 7 "Evaluation of WDM-PON Traffic Protection Schemes" is markedly expanded with the sensitivity analysis presented in more detail. Also, considered specific cases of feasibility margins are defined.

Considering the margin of feasibility‚ Tables 7 and 8 are extended to specific comfortably feasible‚ marginally feasible and infeasible cases․ +0․30 dB cannot be interpreted with the same certainty as +10 dB․

Response: The comment is accepted; Tables 7 and 8 in Section 7 "Evaluation of WDM-PON Traffic Protection Schemes" are extended with a new column where specific cases of feasibility margins are introduced for each architecture type.

Essentially: metro-access: rather than simply closing on the cardinality limits I see‚ I would like to frame this discussion in terms of concrete engineering trade-offs: where to place amplifiers effectively‚ how many of them‚ and/or reducing reach․

Response: We appreciate the Reviewer’s comments. In this paper, presumptive WDM-PON architectures (Section 3) are supposed without optical amplifiers. The placement of optical amplifiers is not the main goal. This discussion can be developed in future research works. Maybe, https://doi.org/10.2478/jee-2020-0043 can serve as the starting point.

Component parameter sourcing: complement the commercial vendor catalog (reference [26]) with literature or standard values for the insertion loss parameters and justify the worst case parameters chosen vs․ ITU-T recommendations.

• Response: The comment is accepted; Subsections 4.3 "Remote nodes" and 4.4 "Other relevant components" are expanded with explanations how values of insertion losses for power splitters, AWG devices and other passive optical components were selected. Selected values from the commercial catalog accurately reflect the real behavior of commercially available components and they are simultaneously complementing with standard values for the insertion loss parameters to justify the worst case for each passive optical component. By this way, the loss model used in the power budget calculations ensures that the total attenuation introduced by these components avoids underestimating. Within this context, and a list of appropriate references is markedly enhanced.

 

Benchmark: numerical cross-validation of the formula results from the Excel/VBA tool against an independent analytical calculation or a published reference scenario should be performed to show computational correctness

Response: The subsection "Research Directions and Future Challenges" is added into the Section 9 “Conclusions”. In this subsection, following sentences are introduced: There are no known papers suitable for a near comparison in terms of the optical power budget analysis in WDM-based passive optical networks. By contrast, a fundamental and elementary base is introduced for another possible analysis of future-constructed WDM-PONs utilizing traffic protection schemes.

Few new contributions to science have been created relative to the author's previous work‚ and self-citation of the reference list is close to 40%․ The core of the paper is in [18] and [19]․ The power budget formulas are standard textbook formulas‚ and the calculations do not appear to have been analytically developed․ In addition‚ the Excel/VBA implementation does not represent a methodological advance over optical link budget packages․ The lack of sensitivity analysis affects the generalizability of the findings․

Response: We appreciate the Reviewer’s opinion. After reading the comment, there is probably a misunderstanding. In the original version of the manuscript, there are 5 (our) references ([6,16,18,19,20]) of the 28, i.e. 17.8% - way ahead of the Reviewer’s 40% value. In this revised version, the self-citation ratio is much lower, 5 of the 49, i.e. 10,2%. We think that the self-citation ratio is at the acceptable level. Based on previous Reviewer’s comments, the common base of our research activities is explained in detail. And the novelty of this submission is also emphasized in the manuscript. Based on previous Reviewer’s comments, the sensitivity analysis is also added.

The paper closes the gap between practically relevant resilience in traffic protection and the optimal optical physical-layer feasibility of bi-directional WDM-PON networks․ The systematic assessment of eight protection variants across three groups of WDM-PON topologies in an interactive simulation tool creates a benchmark for practitioners and researchers in the field․ The paper is generally well organized and clearly written․

We would like to thank the respected Reviewer for his comments and remarks that make our paper better.

Although some issues are dealt with in the manuscript‚ it does not reach the expected level of very high impact factor journal mostly due to a lack of novelty‚ a high percentage of self-citations‚ and the lack of a sensitivity analysis․ The major revision should address the points mentioned above‚ namely‚ the technical differentiation with respect to other works (particularly reference [18])‚ the references‚ decoupling the entire Section 3 and the parametric sensitivity analysis․ If revised as suggested‚ this manuscript should act as a useful contribution to the planning of optical access networks․

We appreciate the Reviewer’s opinion. Maybe, a correct interpretation of the arrangements in the revised manuscript can revise these comments.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors are sincerely thanked for their effort, diligence, and constructive attitude in addressing the comments and suggestions provided by this reviewer. Their willingness to carefully consider and incorporate the feedback has significantly contributed to improving the scientific quality, clarity, and overall rigor of the manuscript. This collaborative and responsive approach is highly appreciated and reflects a commendable commitment to excellence in scientific communication.

Author Response

The authors are sincerely thanked for their effort, diligence, and constructive attitude in addressing the comments and suggestions provided by this reviewer. Their willingness to carefully consider and incorporate the feedback has significantly contributed to improving the scientific quality, clarity, and overall rigor of the manuscript. This collaborative and responsive approach is highly appreciated and reflects a commendable commitment to excellence in scientific communication.

We highly appreciate the Reviewer’s opinion. We'd like to thank the esteemed and respected Reviewer for his regardful reading of the manuscript and for preparing meaningful comments and suggestions. Proactive and  cooperative Reviewer’s contribution in scientific communication made our paper better.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

In order to reach acceptance‚ the paper must show convincingly the added scientific contribution‚ e․g․ by putting novelty vs․ earlier work in a clearer context‚ by adding a proper validation (cross-verification with analytical models‚ comparison with independent tools or scenarios in the literature)․ It should also include a more complete and systematic parametric study for the sensitivity analysis․ Engineering interpretations should also be provided that could include the trade-offs between different options as well as possible design rules․ However claims for when this work was without comparison need to be tempered in comparison with the existing literature and with the differences from the authors' earlier works․

Author Response

In order to reach acceptance‚ the paper must show convincingly the added scientific contribution‚ e․g․ by putting novelty vs․ earlier work in a clearer context‚ by adding a proper validation (cross-verification with analytical models‚ comparison with independent tools or scenarios in the literature)․ It should also include a more complete and systematic parametric study for the sensitivity analysis․ Engineering interpretations should also be provided that could include the trade-offs between different options as well as possible design rules․ However claims for when this work was without comparison need to be tempered in comparison with the existing literature and with the differences from the authors' earlier works․

We appreciate the Reviewer’s opinion, comments, and remarks. We hold the view that these comments and suggestions are already addressed in the manuscript. Detailed responses are provided below. Relevant parts in the revised manuscript are highlighted (red text font color with yellow text highlight color). We would like to thank the respected Reviewer for his comments and remarks that make this paper better.

 

• comparison with existing literature, cross-verification with scenarios in the literature
• Response: These comments are accepted – Rows 115-127 and References [3]-[22] in Section 1 "Introduction". Based on the reviewed literature, current research on optical power budget analysis can be divided into several main directions, no one is oriented on the optical power budget consideration of traffic protection schemes for advanced WDM-PON networks.
• cross-verification with analytical models‚ comparison with independent tools
• Response: Based on previous response, there are no known analytical models and independent tools suitable for a near comparison and cross-verification in terms of the optical power budget analysis in WDM-based traffic protection schemes.

 

• comparison with the differences from the authors' earlier works
• Response: The comment is accepted – Rows 128-136 in Section 1 "Introduction" are devoted to the common research base of our earlier works . Rows 137-174 in Section 1 "Introduction" describe main contributions of previous submissions. Rows 175-182 in Section 1 "Introduction" identify a novelty of this work that is characterized in Rows 196-208 in Section 2 "Materials and Methods". Rows 575-586 in Section 9 "Conclusions" present new findings of the paper’s novelty that can determine future research directions.

 

• a more complete and systematic parametric study for the sensitivity analysis
• Response: The comment is accepted – Rows 310-315 in Section 4 "WDM-PON Components and their Power Budget Parameters". The study for the sensitivity analysis is not the main goal of this manuscript. In our WDM-PON Network Power Budget Evaluator, we reflect receiver sensitivity parameters for given data rate, line code and requested BER value based on standard [30], commercial [33] and scientific references [16,19,21]. In case of changes in data rate and/or line code parameters applied at the optical transmission, corresponding incurred additional receiver penalty can be easily entered into the power budget calculated in the simulation tool.

We hope that any concrete remarks of the respected Reviewer were accommodated in this paper.

Author Response File: Author Response.pdf