A Control Plane Architecture for Multi-Domain Elastic Optical Networks: The View of the IDEALIST Project

A key objective of the IDEALIST project included the design and implementation of a GMPLS and PCE-based control plane for multi-vendor and multi-domain flexi-grid EON, leveraging the project advances in optical switching and transmission technology, an enabling interoperable deployment. A control plane, relying on a set of entities, interfaces, and protocols, provides the automation of the provisioning, recovery, and monitoring of end-to-end optical connections. This article provides an overview of the implemented architecture. We present the macroscopic system along with the core functional blocks, control procedures, message flows, and protocol extensions. The implemented end-to-end architecture adopted active stateful hierarchical PCE, under the control and orchestration of an adaptive network manager, interacting with a parent PCE, which first coordinates the selection of domains and the end-to-end provisioning using an abstracted view of the topology, and second, delegates the actual computation and intra-domain provisioning to the corresponding children PCEs. End-to-end connectivity is obtained by either a single LSP, or by the concatenation of multiple LSP segments, which are set up independently by the underlying GMPLS control plane at each domain. The architecture and protocol extensions have been implemented by several partners, assessing interoperability in a multi-partner testbed and adoption by the relevant Internet SDO (standards development organization).