Hierarchical Distributed Topology Discovery Protocol for Multi-Domain SDN Networks

This letter presents a hierarchical distributed topology discovery protocol on the use of hierarchical path computation elements (PCEs) for orchestrating multi-domain software-defined networking. The challenge of this protocol is how child PCEs can maintain an abstract inter-domain topology while preserving intra-domain confidential information in a hierarchical PCE-based orchestration architecture. The experimental results show that the proposed protocol evenly distributes path computation burden among all child PCEs compared with the hierarchical PCE approach. The proposed protocol considerably reduces the provisioning delay compared with the distributed approach while preserving confidential intra-domain information.