Design and Performance Insights in Backbone Node Upgrades: From Single-Band WSS to UWB-Based Flex-WBSS Solutions
Year: 2025
Type: article
Abstract: Emerging services such as artificial intelligence (AI), 5G, the Internet of Things (IoT), cloud data services and teleworking are growing exponentially, pushing bandwidth needs to the limit. Space Division Multiplexing (SDM) in the spatial domain, along with Ultra-Wide Band (UWB) transmission in the spectrum domain, represent two degrees of freedom that will play a crucial role in the evolution of backbone optical networks. SDM and UWB technologies necessitate the replacement of conventional Wave-length-Selective-Switch (WSS)-based architectures with innovative optical switching elements capable of handling both higher port counts and flexible switching across various granularities. In this work, we introduce a novel Photonic Integrated Circuit (PIC)-based switching element called flex-Waveband Selective Switch (WBSS), designed to provide flexible band switching across the UWB spectrum (~21 THz). The proposed flex-WBSS supports a hierarchical three-layered Multi-Granular Optical Node (MG-ON) architecture incorporating optical switching across various granularities ranging from entire fibers, flexibly defined bands down to individual wavelengths. To evaluate its performance, we develop a custom network simulator, enabling a thorough performance analysis on all node’s critical performance metrics. Simulations are conducted over an existing network topology evaluating three traffic-oriented switching policies: Full Fiber Switching (FFS), Waveband Switching (WBS), and Wavelength Switching (WS). Simu-lation results reveal high Optical to Signal Ratio (OSNR) and low Bit Error Rate (BER) values, particularly under the FFS policy. In contrast, the integration of the WBS policy bridges the gap between existing WSS- and future FFS-based architectures, manages to relax bandwidth demands and mitigates capacity bottlenecks enabling rapid scalable network upgrades in existing infrastructures. Additionally, we propose a probabilistic framework to evaluate the node’s bandwidth utilization and scaling behavior, exploring tradeoffs among scalability, components’ number and complexity. The proposed framework can be easily adapted for the design of future transport optical networks. Finally, we perform a SWaP-C (Size, Weight, Power and Cost) analysis to underscore the advantages of the proposed architecture. Our results confirm that the proposed node incorporating PIC-based flex-WBSSs, prove to be a cost- and power-efficient solution compared to its counterparts, as reduce excessive initial network deployment/upgrade costs while at the same time minimizing power resource requirements.
Source: Telecom
Authors: Charalampos Papapavlou, Konstantinos Paximadis, Dan M Marom, Ioannis Tomkos
Institutions: University of Patras, Hebrew University of Jerusalem
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,448
OpenAlex ID: W7109954346