BSSN-SDNs: A Blockchain-Based Security Service Negotiation for the SDN Interdomain

The security requirements for SDN (Software-Defined Network) cross-domain communication are diverse and dynamically changing; thus, a security service negotiation function is required for the SDN interdomain. However, the SDN interdomain distributed communication environment leads to a lack of trustworthiness and security. Therefore, this paper proposes a blockchain-based SDN interdomain security service negotiation mechanism, BSSN-SDNs, to provide automatic, secure, and trustworthy SDN interdomain security service negotiation. BSSN-SDNs proposes a three-layer reference architecture that enables joint on-chain and off-chain work by extending the security service negotiation module and blockchain client on the controller and deploying security service negotiation smart contracts on the blockchain. It especially adopts non-interactive key exchange and the message authentication code to ensure the confidentiality of the secure service negotiated on-chain. Finally, the timeliness as well as security and trustworthiness of BSSN-SDNs are analyzed, and the FISCO BCOS-based experiment results show that the delay of BSSN-SDNs is acceptable and is positively correlated with the number of policies and the number of SDN domains involved in negotiation.