Flexnetic: Cost-Effective and Smooth Evolution of Optical Backbone

The increasing traffic on WANs due to growing number of applications imposes significant strain on the infrastructure of cloud service providers. The primary expense in augmenting network capacity entails high costs associated with procuring expensive transponders that facilitate inter-regional optical signal transmission. The advent of spacing variable transponders facilitates cost-effective network upgrades and increased transmission efficiency, however, implementing such upgrades in one step may incur high costs and service disruptions. Achieving a cost-effective and smooth network upgrade presents considerable challenges in identifying critical IP links and minimizing costs within existing architecture. We introduce Flexnetic, a planning tool which utilizes a hybrid approach of both modern and legacy transponders, along with establishment of optical bypass, to accommodate the escalating traffic demands while minimizing the costs during network upgrades. Flexnetic incorporates two novel algorithms: a NLP model to maximize IP link capacity utilization, and an MIP model for efficient IP layer implementation at optical layer, emphasizing reuse of existing transponder and minimizes new device requirement. Our simulation of upgrade plans on common WAN topologies revealed superior performance, with up to 91.9% cost savings and 2.33× capacity increase over existing state-of-the-art solutions, highlighting Flexnetic’s potential for cost-efficient and capacity-optimized network upgrades.