C+L-band upgrade strategies to sustain traffic growth in optical backbone networks

Abstract

We investigate cost-efficient upgrade strategies for capacity enhancement in optical backbone networks enabled by C+L-band optical line systems. A multi-period strategy for upgrading network links from the C band to the C+L band is proposed, ensuring physical-layer awareness, cost effectiveness, and less than 0.1% blocking. Results indicate that the performance of an upgrade strategy depends on efficient selection of the sequence of links to be upgraded and on the time instant to upgrade, which are either topology or traffic dependent. Given a network topology, a set of traffic demands, and growth projections, our illustrative numerical results show that a well-devised upgrade strategy can achieve superior cost efficiency during the capacity upgrade to C+L enhancement.

Flexible Technologies to Increase Optical Network Capacity

“…The network performance of BT-UK network shown in Fig. 3 [7] has been evaluated in Fig. 4 which gives an example of the effect of fine spectral control to increase spectral efficiency while considering traffic matrices generated using 100 seeds with uniform distribution for selecting source and destination pairs and considering fixed connection requests of 100 Gb/s [8].…”

“…13: Normalised cost-per-bit performance of Indian Network with variation in fibre lease cost mum spectrum provisioning and management strategy may be beneficial for operators: deferral should benefit from cheaper network equipment. A similar strategy was proposed in [7] where maximum cost benefits were available while choosing network link upgrade based on highest spectral utilisation per link.…”

C to C+L Bands Upgrade with Resource Re-provisioning in Optical Backbone Networks

“…We use an upgrade strategy based on two steps [7], forming the basis of our re-provisioning strategy in Section 3.…”

“…• Link-Selection Technique: We employ a multi-period strategy where, periodically, a batch of 'highlyutilized links' are selected for upgrade, as this leads to most cost efficiency [7]. • Upgrade-Time-Selection Technique: To handle traffic growth, when to upgrade (Year/Quarter?)…”

“…Total cost is calculated by adding equipment cost and subtracting CAPEX deferral. Details of the upgrade strategy and cost model can be found in [7]. In this work, we focus on the impact of re-provisioning on an upgrade strategy.…”