Cloud Data-Center Network Verification: Approaches, Algorithms and Toolchains

The Cloud data center networks are the foundation of the modern cloud computing since they allow access to distributed virtualized resources on demand, at scale, and at reasonable costs. With the rapidly rising cloud services, however, new serious concerns have arisen that were associated with energy consumption, security, correctness, and reliability of the large-scale networked infrastructures. This paper gives a detailed analysis of verification methods in cloud data center networks, including static, dynamic and runtime verification methods. The techniques that can be used to identify configuration errors and policy errors before implementation are discussed as static techniques like header space analysis, SMT/SAT-based verification, and graph-based analysis. It is examined using dynamic and runtime methods, such as telemetry-based verification, invariant mining and misconfiguration detection methods to handle dynamic network behaviors and security threats over operational settings. The paper also covers the theoretical base of these techniques, and focus on SMT solvers, symbolic execution, and logical attestation to enforce correctness and access control. Moreover, the achieved tools chains and real-life applications of academic literature, industry cloud vendors, and open-source SDN environments are examined to reflect their strengths and weaknesses.