A stateful PCE-based carrier-grade transport network: Design, implementation, evaluation, and experiences

This paper describes the experience of designing, implementing, and evaluating a carrier-grade transport network with stateful path computation element (PCE) extensions. The key concept is to develop an implementation framework for future extensions of the stateful PCE architecture to support carrier-grade transport services. The proposed framework combines a centralized provisioning controller and distributed management entities to meet the requirements both of network operators and carrier-grade transport services. To validate the feasibility of the framework, two testbeds, an emulation testbed and an integration testbed, are implemented and evaluated via functional, operational, and interoperable testing by exploiting a combinatorial testing approach. The evaluation results indicate that this combinatorial testing reduces the significant risks of protocol defects, accelerates the development cycle, improves protocol quality, and ensures interoperability in a structured and integrated manner. The evaluations of these two testbeds complement each other to build an evolving architecture. This paper describes specific lessons for a control plane developer working with a design, testbed implementation, and evaluation architecture.