Application of S-band for Protection in Multi-band Flexible-Grid Optical Networks

TL;DR

The work tackles bandwidth capacity and survivability in optical networks by adopting a Multi-band Flexible-grid approach that uses C+L-band for working traffic and S-band for protection. It introduces a QoT-driven RSA and protection provisioning framework where $k$-shortest paths are computed with Dijkstra, spectrum is allocated first in C-band then in L-band, and GOSNR QoT is validated via $\text{GOSNR}$ (using $\text{GNPy}$). A working path is protected by a link-disjoint S-band backup path when $A_w < A_{th}$, using a Shared Backup Path and Slots Protection technique to enable rapid failover. The scheme is evaluated in terms of spectrum occupancy (e.g., $12.5$ GHz grid yielding $868$ working slots ($548$ in L-band, $320$ in C-band) and $732$ backup slots in S-band) and is contrasted with SSMF and core-based networks, highlighting potential capacity and resilience improvements through multi-band resources.

Abstract

The core network is experiencing bandwidth capacity constraints as internet traffic grows. As a result, the notion of a Multi-band flexible-grid optical network was established to increase the lifespan of an optical core network. In this paper, we use the C+L band for working traffic transmission and the S-band for protection against failure. Furthermore, we compare the proposed method with the existing ones.

Figures (1)

• Figure 1: Flowchart of the proposed scheme.