This paper proposes an adaptive communication management method based on Software-Defined Networking (SDN) and blockchain for the Trustworthy On-chain and Off-chain Interoperability System. By leveraging the security advantages of blockchain, this approach constructs a secure, decentralized SDN control system for managing the communication network. The system facilitates adaptive management modules that can autonomously detect failed gateways, select candidate gateways with low load for data transmission, and ensure the repair of data transmission paths when the off-chain network state undergoes changes. Furthermore, each SDN controller serves as a redundant component; in the event of a controller failure, others seamlessly assume its operations, thereby ensuring sustained communication reliability.