On QoS-assured degraded provisioning in service-differentiated multi-layer elastic optical networks

TL;DR

This paper proposes novel online degraded provisioning algorithms for multi-layer elastic optical networks, improving service reliability and capacity by leveraging QoS guarantees through service-holding-time prolongation and immediate access.

Contribution

It introduces polynomial-time algorithms for degraded routing and resource allocation in multi-layer elastic optical networks with QoS guarantees, enhancing network flexibility and performance.

Findings

Significant reduction in service failures, especially for high-priority requests.

Degradation in optical layer increases network capacity.

Degradation in electric layer enables flexible time-bandwidth exchange.

Abstract

The emergence of new network applications is driving network operators to not only fulfill dynamic bandwidth requirements, but offer various grades of service. Degraded provisioning provides an effective solution to flexibly allocate resources in various dimensions to reduce blocking for differentiated demands when network congestion occurs. In this work, we investigate the novel problem of online degraded provisioning in service-differentiated multi-layer networks with optical elasticity. Quality of Service (QoS) is assured by service-holding-time prolongation and immediate access as soon as the service arrives without set-up delay. We decompose the problem into degraded routing and degraded resource allocation stages, and design polynomial-time algorithms with the enhanced multi-layer architecture to increase the network flexibility in temporal and spectral dimensions. Illustrative results verify that we can achieve significant reduction of network service failures, especially for requests with higher priorities. The results also indicate that degradation in optical layer can increase the network capacity, while the degradation in electric layer provides flexible time-bandwidth exchange.