Modeling and Verifying OpenFlow Scheduled Bundle Mechanism Using CSP

OpenFlow is considered as one of the first standard of software defined networking (SDN). The OpenFlow scheduled bundle mechanism is a latest mechanism proposed in OpenFlow protocol to guarantee the completeness and consistency of messages transimitted between SDN switches and controllers during the communication process. Due to the requirement of reliability and security, it is of great significance to formally analyze and verify the mechanism. In this paper, we apply Communication Sequential Processes (CSP) and use the model checker Process Analysis ToolKit (PAT) to model and verify the OpenFlow scheduled bundle mechanism. We verify the main property of the mechanism, schedulability. In addition, we analyze and verify the security of the mechanism and find that it suffers from some kinds of possible attacks.