arxiv: 2605.05793 · v1 · submitted 2026-05-07 · 💻 cs.NI

Recognition: unknown

Bridging the 6G Gap: Scaling Sustainable ROADM-Based IP-over-WDM via DSCM-Enabled Point-to-Multipoint Designs

Matin Rafiei Forooshani , Farhad Arpanaei , Hamzeh Beyranvand , Mahdi Ranjbar Zefreh , Juan Pedro Fern\'andez-Palacios , Alfonso S\'anchez-Maci\'an , Jos\'e Alberto Hern\'andez , David Larrabeiti

Authors on Pith no claims yet

Pith reviewed 2026-05-08 05:15 UTC · model grok-4.3

classification 💻 cs.NI

keywords 6GIP-over-WDMROADMPoint-to-MultipointDSCMCAPEXpower efficiencysustainable networking

0 comments

The pith

DSCM-based point-to-multipoint IP-over-WDM cuts CAPEX by 92 percent and power by 99 percent over ten years versus point-to-point designs.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper compares transponder-based point-to-point and DSCM-based point-to-multipoint architectures for ROADM-supported IP-over-WDM networks in access and metro segments. It shows that the point-to-multipoint version delivers large efficiency gains across varied geographic types. These gains matter for scaling 6G networks because they must support much higher traffic while controlling both upfront costs and ongoing energy use. The ten-year horizon simulations project the savings hold across different scenarios. A reader focused on practical deployment would see this as evidence that resource-sharing designs can make high-capacity optical networks viable for widespread 6G rollout.

Core claim

DSCM-enabled Point-to-Multipoint (PtMP) IPoWDM architectures optimize efficiency across diverse geotypes by slashing CAPEX by 92.0 percent and power consumption by 99.2 percent compared to the traditional point-to-point benchmark over a ten-year horizon.

What carries the argument

DSCM-based Point-to-Multipoint (PtMP) access-metro architecture, which shares transponder and ROADM resources among multiple endpoints instead of dedicating separate equipment to each link.

Load-bearing premise

The traffic patterns, equipment cost models, power consumption figures, and geotype classifications used in the ten-year simulations accurately represent real-world conditions and future 6G demands.

What would settle it

A field deployment or updated simulation using measured 6G traffic and actual vendor pricing that yields CAPEX savings below 80 percent or power savings below 90 percent over ten years would undermine the central claim.

Figures

Figures reproduced from arXiv: 2605.05793 by Alfonso S\'anchez-Maci\'an, David Larrabeiti, Farhad Arpanaei, Hamzeh Beyranvand, Jos\'e Alberto Hern\'andez, Juan Pedro Fern\'andez-Palacios, Mahdi Ranjbar Zefreh, Matin Rafiei Forooshani.

**Figure 1.** Figure 1: Network topologies for the evaluated geotypes in the ALLEGRO reference network: (a) Dense Urban, (b) Urban, (c) Suburban, and (d) Rural view at source ↗

**Figure 2.** Figure 2: Node architecture of (a) Benchmark (gray) scenario, (b) PtP-AtM IPoWDM, (c) PtMP-AtM IPoWDM Quality of Transmission (QoT) Estimation QoT is evaluated using segment-specific metrics. For AtM, we use 50 GHz channel spacing and 27.95 GBaud symbol rate, deploying 100G DSCM for PtMP-AtM and 100G ZR for PtP-AtM. Neglecting nonlinearities in short spans, performance is assessed via OSNR = Prx/PASE, where Prx = P… view at source ↗

**Figure 3.** Figure 3: (a) Total cost and (c) power consumption breakdown by element in the MtC network, where percentages indicate the relative contribution of each component to the segment total. (b) Total cost and (d) power consumption in the AtM segment; here, percentages denote the relative difference between the lower and higher values across the evaluated scenarios view at source ↗

**Figure 4.** Figure 4: (a) Number of elements deployed in the AtM network under three scenarios, (b) The relative difference between scenarios. ferences. In the Benchmark scenario, 876 leaf nodes use 100G gray transceivers (860 LR, 16 ER), requiring 1,356 additional 100G LR modules and 872 CO transponders for aggregation. The PtP-AtM replaces this hierarchy with 100G ZR transceivers at both ends, whereas PtMP-AtM further reduce… view at source ↗

read the original abstract

This study compares transponder-based, Point-to-Point, and DSCM-based Point-to-Multipoint (PtMP) access-metro architectures. Findings demonstrate that PtMP IPoWDM significantly optimizes efficiency across diverse geotypes, slashing CAPEX by 92.0% and power by 99.2% compared to the traditional benchmark over a ten-year horizon.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

The paper applies DSCM to PtMP in ROADM IP-over-WDM and reports 92% CAPEX plus 99% power cuts, but those figures rest on un-sourced simulation inputs that lack validation or sensitivity checks.

read the letter

The headline result is that DSCM-enabled point-to-multipoint designs in IP-over-WDM ROADM networks deliver very large efficiency gains over ten years across geotypes compared with conventional point-to-point transponder setups. The work takes existing digital subcarrier multiplexing ideas and shows how they can support PtMP operation in access-metro segments, cutting the number of dedicated transponders and associated resources. That is a focused, practical step rather than a new theoretical framework, and the comparison across different geotypes gives network planners something concrete to consider for 6G scaling and sustainability targets. The architecture discussion and the long-term projection are the parts that hold up on their own terms. The main weakness is that the quantitative claims depend on equipment cost, power consumption, and traffic models whose origins are not clearly documented or cross-checked against public data sheets. The abstract gives no simulation methodology, no input data sources, and no sensitivity tables, so it is impossible to tell how much the reported deltas would shrink if those parameters moved by even 15-20 percent. If the full paper uses internal vendor figures without external validation, the central numbers stay hard to trust. This is the sort of work that optical-networking and 6G infrastructure researchers might want to see, but only after the assumptions are made reproducible. A reader already working on cost modeling for metro networks could extract the architecture comparison, yet would have to treat the savings percentages as provisional. I would send the paper to peer review rather than desk-reject it. The topic is timely for sustainable high-capacity networks, and referees could require the authors to publish the model parameters and run sensitivity tests, which would turn the current draft into something more usable.

Referee Report

2 major / 1 minor

Summary. The manuscript compares traditional transponder-based point-to-point (PtP) and DSCM-enabled point-to-multipoint (PtMP) architectures for ROADM-based IP-over-WDM networks in 6G contexts. It claims that PtMP designs deliver substantial efficiency gains across geotypes, including 92.0% CAPEX reduction and 99.2% power savings relative to the PtP benchmark over a ten-year horizon.

Significance. If the underlying models prove accurate, the reported savings could meaningfully inform sustainable scaling strategies for 6G optical transport, particularly in access-metro segments where power and capital efficiency are critical. The work identifies PtMP as a potential lever for reducing both OPEX and environmental footprint in diverse deployment scenarios.

major comments (2)

[Abstract and Results sections] The quantitative headline results (92.0% CAPEX and 99.2% power savings) are presented without any description of the simulation methodology, traffic matrices per geotype, equipment cost models, power consumption figures, discount rates, or validation steps. This is load-bearing for the central claim because the deltas rest entirely on the realism of these inputs; even moderate optimism in PtMP efficiencies or inflation in the traditional benchmark would collapse the reported gains.
[Simulation Setup and Parameterization] No sensitivity analysis, citation trail to public data sheets, or cross-check against independent measurements is provided for the proprietary or internal vendor-derived transponder costs, DSCM PtMP power draw, and geotype classifications used in the ten-year simulations. This directly undermines confidence in the 92%/99.2% figures as stated in the abstract.

minor comments (1)

[Abstract] The abstract would be strengthened by a single sentence summarizing the key modeling assumptions or data sources to allow immediate contextualization of the quantitative claims.

Simulated Author's Rebuttal

2 responses · 1 unresolved

We thank the referee for the constructive comments highlighting the need for greater methodological transparency to support our reported efficiency gains. We have revised the manuscript accordingly to address these points while preserving the integrity of the analysis.

read point-by-point responses

Referee: [Abstract and Results sections] The quantitative headline results (92.0% CAPEX and 99.2% power savings) are presented without any description of the simulation methodology, traffic matrices per geotype, equipment cost models, power consumption figures, discount rates, or validation steps. This is load-bearing for the central claim because the deltas rest entirely on the realism of these inputs; even moderate optimism in PtMP efficiencies or inflation in the traditional benchmark would collapse the reported gains.

Authors: We agree that the abstract and results sections require additional context on the simulation methodology to make the claims self-contained. In the revised manuscript, we have expanded the abstract with a high-level overview of the ten-year TCO simulation framework, including geotype-specific traffic matrix generation, equipment cost and power models, and the applied discount rate. The results section now includes a concise summary of these elements along with validation against established network benchmarks, directing readers to the detailed methods for full parameterization. revision: yes
Referee: [Simulation Setup and Parameterization] No sensitivity analysis, citation trail to public data sheets, or cross-check against independent measurements is provided for the proprietary or internal vendor-derived transponder costs, DSCM PtMP power draw, and geotype classifications used in the ten-year simulations. This directly undermines confidence in the 92%/99.2% figures as stated in the abstract.

Authors: We acknowledge the value of explicit sensitivity analysis and traceable sources. The revised manuscript adds a 'Model Parameters and Sensitivity Analysis' subsection that provides citations to publicly available data sheets for baseline transponder costs and power figures, justifies geotype classifications with references to standard planning guidelines, and includes sensitivity results varying traffic growth, cost assumptions, and efficiency parameters by ±20%. These show the savings remain robust (exceeding 80% CAPEX and 95% power reduction) under conservative inputs. However, exact proprietary vendor cost models and raw DSCM measurements cannot be fully disclosed due to confidentiality constraints; ranges and bounding assumptions are provided instead. revision: partial

standing simulated objections not resolved

Full public disclosure of proprietary vendor-derived transponder cost models and exact DSCM power consumption measurements, which are subject to non-disclosure agreements.

Circularity Check

0 steps flagged

No circularity: simulation outputs rest on external input models, not self-referential derivations

full rationale

The paper is a comparative simulation study of PtP vs. PtMP IPoWDM architectures across geotypes, reporting 10-year CAPEX and power deltas as direct simulation results. No equations, fitted parameters, or predictions appear that reduce by construction to the same inputs (e.g., no self-definitional scaling factors or 'predictions' of ratios derived from the fitted costs themselves). Input models for equipment costs, power draw, traffic matrices, and discount rates are treated as given assumptions whose realism is an external validity question, not a circularity issue. No self-citation load-bearing uniqueness theorems, ansatzes smuggled via prior work, or renaming of known results are present. The derivation chain is therefore self-contained as a forward simulation rather than a closed loop.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

No details on free parameters, axioms, or invented entities are available from the abstract alone.

pith-pipeline@v0.9.0 · 5414 in / 1058 out tokens · 41959 ms · 2026-05-08T05:15:37.429164+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

19 extracted references · 8 canonical work pages

[1]

Migration strategies from C-band to C+L-band/multi-fiber solutions in optical metropolitan area networks

F . Arpanaeiet al., “Migration strategies from C-band to C+L-band/multi-fiber solutions in optical metropolitan area networks”, in 49th European Conference on Op- tical Communications (ECOC 2023) , vol. 2023, 2023, pp. 1531–1534. DOI: 10.1049/icp.2023.2620

work page doi:10.1049/icp.2023.2620 2023
[2]

Attenuation-resilient 1-gbit/s ook underwater free-space optical communications using a longitudinally structured multi-kz bessel beam

A. Napoli, C. Castro, P . Torres-Ferrera,et al., “Towards truly scalable sustainable flexible optical networks”, in 2025 European Conference on Optical Communications (ECOC), 2025, pp. 1–4. DOI: 10.1109/ECOC66593.2025. 11263099

work page doi:10.1109/ecoc66593.2025 2025
[3]

Extended net- work applications of coherent pluggable transceivers [invited]

J. Pedro, M. M. Hosseini, and A. Napoli, “Extended net- work applications of coherent pluggable transceivers [invited]”,Journal of Optical Communications and Net- working, vol. 17, no. 2, A210–A223, 2025.DOI: 10.1364/ JOCN.537601

2025
[4]

Leveraging the potential of coherent pluggable transceivers across diverse network applications

J. Pedro, “Leveraging the potential of coherent pluggable transceivers across diverse network applications”, inAd- vanced Photonics Congress (IPR, Networks, NOMA, SOLITH, SPPCom) , Optica Publishing Group, 2025, NeTu2C.5. DOI: 10 . 1364 / NETWORKS . 2025 . NeTu2C

2025
[5]

Available: https : / / opg

[Online]. Available: https : / / opg . optica . org / abstract.cfm?URI=Networks-2025-NeTu2C.5

2025
[6]

Digital subcarrier multiplexing: Enabling software-configurable optical networks

D. Welch et al., “Digital subcarrier multiplexing: Enabling software-configurable optical networks”,Journal of Light- wave Technology, 2023. DOI: 10 . 1109 / JLT . 2022 . 3211466

2023
[7]

On clustering coherent optics point-to-multipoint trees for cost-effective bandwidth assignment in MANs

J. A. Hernandez, F . Arpanaei, A. Napoli, C. Castro, O. Gonzalez de Dios, and J. P . Fernandez-Palacios, “On clustering coherent optics point-to-multipoint trees for cost-effective bandwidth assignment in MANs”, Jour- nal of Optical Communications and Networking, vol. 15, no. 12, pp. 999–1007, 2023. DOI: 10 . 1364 / JOCN . 497459

2023
[8]

Optimized design of horseshoe-and-spur filter- less networks leveraging point-to-multipoint coherent pluggable transceivers

M. M. Hosseini, J. Pedro, N. Costa, C. Castro, and A. Napoli, “Optimized design of horseshoe-and-spur filter- less networks leveraging point-to-multipoint coherent pluggable transceivers”,Journal of Optical Communi- cations and Networking, vol. 16, no. 10, pp. 969–980,
[9]

DOI: 10.1364/JOCN.529546

work page doi:10.1364/jocn.529546
[10]

Power and spectral savings in metro-aggregation networks exploiting coherent point-to- multipoint transceivers

C. Castro et al. , “Power and spectral savings in metro-aggregation networks exploiting coherent point-to- multipoint transceivers”, inECOC 2024; 50th European Conference on Optical Communication, 2024, pp. 519–

2024
[11]

DOI: 10.5281/zenodo.14628563

work page doi:10.5281/zenodo.14628563
[12]

Transceiver guidelines for energy-efficient horseshoes based on digital subcarrier multiplexing

C. Castro, P . Torres-Ferrera, M. Hosseini, and A. Napoli, “Transceiver guidelines for energy-efficient horseshoes based on digital subcarrier multiplexing”, in Advanced Photonics Congress (IPR, Networks, NOMA, SOLITH, SPPCom), Optica Publishing Group, 2025, NeTu1C.2. DOI: 10.1364/NETWORKS.2025.NeTu1C.2

work page doi:10.1364/networks.2025.netu1c.2 2025
[13]

Power consumption considerations of coherent transceivers in filterless point-to-multipoint metro-aggregation networks with digital subcarrier multiplexing

C. Castro, P . Torres-Ferrera, M. S. Erkilinç,et al., “Power consumption considerations of coherent transceivers in filterless point-to-multipoint metro-aggregation networks with digital subcarrier multiplexing”, J. Opt. Commun. Netw., vol. 17, no. 6, pp. 526–542, Jun. 2025. DOI: 10. 1364/JOCN.559237

2025
[14]

Design of filterless horseshoe networks optimized for inter- operable coherent pluggable transceivers

F . Gatti, J. Pedro, N. Costa, and L. Cancela, “Design of filterless horseshoe networks optimized for inter- operable coherent pluggable transceivers”,Photonics, vol. 13, no. 3, 2026, ISSN : 2304-6732. DOI: 10.3390/ photonics13030272

2026
[15]

ALLEGRO Consortium, ALLEGRO project: Agile ultra low energy secure networks, https://www.allegro- he.eu/, Accessed: 2026-03-24, 2026

2026
[16]

A generalized cost model for techno- economic analysis in optical networks

A. Souza et al., “A generalized cost model for techno- economic analysis in optical networks”, Photonics, vol. 13, no. 2, 2026, ISSN : 2304-6732. DOI: 10.3390/ photonics13020125

2026
[17]

Enabling seamless migration of opti- cal metro-urban networks to the multi-band: Unveiling a cutting-edge 6d planning tool for the 6g era

F . Arpanaeiet al., “Enabling seamless migration of opti- cal metro-urban networks to the multi-band: Unveiling a cutting-edge 6d planning tool for the 6g era”,Journal of Optical Communications and Networking, vol. 16, no. 4, pp. 463–480, 2024. DOI: 10.1364/JOCN.505490

work page doi:10.1364/jocn.505490 2024
[18]

TEFNET24: Reference packet optical network topology for edge to core trans- port

J. M. Rivas-Moscoso et al. , “TEFNET24: Reference packet optical network topology for edge to core trans- port”,Journal of Optical Communications and Network- ing, 2024. DOI: 10.1364/JOCN.533131

work page doi:10.1364/jocn.533131 2024
[19]

J. M. Rivas Moscoso and M. Quagliotti, SEASON Access-Metro Reference Network Topology, version v2, Zenodo, 2025. DOI: 10.5281/zenodo.17183654 . [On- line]. Available: https://doi.org/10.5281/zenodo. 17183654

work page doi:10.5281/zenodo.17183654 2025