Decentralized Trust and Dynamic Batching for Multi-Domain SDN Using Blockchain

In multi-domain network environments, each domain operates with its own Software-Defined Networking (SDN) controller, making it challenging to ensure secure and consistent topology management across domains. Traditional centralized logging systems fall short in providing the transparency, flexibility, and decentralized trust needed for effective collaboration between controllers. Distributed Ledger Technologies (DLT) offer a decentralized and immutable way to log network operations, presenting a promising solution for multi-domain SDN environments. This paper presents an approach that uses blockchain to record topology management operations such as adding, updating, and deleting devices and links across multiple SDN domains. The framework leverages permissioned blockchains to establish decentralized trust, with SDN controllers acting as validator nodes to validate and commit transactions upon reaching consensus. An Adaptive Batch Mechanism (ABM) is introduced to optimize block formation by dynamically adjusting batch parameters and using dummy transactions to maintain efficiency during low and varying transaction loads. Experimental validation using Hyperledger Fabric demonstrates the system’s ability to enhance decentralized logging, reduce delays in transaction processing, and facilitate inter-domain coordination while maintaining robust security through a distributed trust model.