Filterless Optical Networks Research Articles

1+1 Dedicated Optical-Layer Protection Strategy for Filterless Optical Networks

We propose a dedicated optical-layer protection strategy for filterless optical networks offering a 100% protection ratio by introducing a limited number of wavelength selective components at selected intermediate nodes. A comparison with conventional active photonic switching networks is presented. The results show that the proposed 1+1 protection for filterless networks exhibits a clear cost advantage at similar wavelength usage compared to active switching solutions.

Establishment of Dynamic Lightpaths in Filterless Optical Networks

In this paper, we study the performance of dynamic routing and wavelength assignment (RWA) in filterless optical networks. These types of broadcast and select networks benefit from breakthroughs in advanced transmission technologies for replacing optical filters and active photonic switching devices, such as wavelength selective switches, with passive optical interconnections between nodes, creating passive optical light trees. We introduce an RWA scheme for establishing passive optical lightpaths in a filterless context and managing unfiltered channels at intermediate egress nodes, which, by propagating downstream of the terminating nodes, participate in wavelength usage and increase the risk of wavelength exhaustion. Simulation results are presented for six network topologies, along with the performance evaluation of active photonic and filterless optical network solutions with static and dynamic RWA schemes. We show that the performance of the proposed scheme depends on the average degree of node connectivity.

Passive filterless core networks based on advanced modulation and electrical compensation technologies

In this paper, the filterless optical network concept is presented and explored through a number of filterless solution examples. In the first part, the filterless network concept is presented and analyzed through a comparative case study. In the second part, the filterless network design problem is defined and a filterless network design tool based on metaheuristics is presented. In the third part of this presentation, filterless network solutions are proposed for a number of core network topologies and compared to active photonic network solutions from the point of view of cost and performance. The results show that cost-effective filterless solutions can be found for different network sizes and topologies. The results of a comparative study show that filterless networks represent a cost-effective and reliable alternative to active optical switching network solutions.

PCE-based centralized control plane for filterless networks

In this article, we present the concept of the filterless optical network from a control plane perspective, defining the network and showing to what extent a control plane could be adapted to it. Then we propose a control plane architecture and study its performance. Filterless networks act as passive broadcast and select networks, in which active switching elements, such as the wavelength selection switch, are replaced by passive optical splitters and combiners, and network agility is provided by tunable transceivers. We introduce the concept of unfiltered channels and that of backward and forward ports, and show how they impact topological performance, and, in particular, the fact that wavelength usage increases greatly as the protection ratio shrinks.

Design and Simulation of Filterless Optical Networks: Problem Definition and Performance Evaluation

Filterless optical networks based on advanced transmission technologies and passive optical interconnections between nodes offer a lower-cost alternative to optical networks based on active photonic switching. A design and simulation platform is proposed for studying these novel network architectures and looking at their performance characteristics. Simulation results are presented for three reference network topologies, along with a comparative cost and performance study of active photonic and passive filterless optical network solutions.