In software-defined networking (SDN), controllers are sinks of information such as network topology collected from switches. Organizations often like to protect their internal network topology and keep their network policies private. We borrow techniques from secure multi-party computation (SMC) to preserve the privacy of policies of SDN controllers about status of routers. On the other hand, the number of controllers is one of the most important concerns in scalability of SMC application in SDNs. To address this issue, we formulate an optimization problem to minimize the number of SDN controllers while considering their reliability in SMC operations. We use Non-Dominated Sorting Genetic Algorithm II (NSGA-II) to determine the optimal number of controllers, and simulate SMC for typical SDNs with this number of controllers. Simulation results show that applying the SMC technique to preserve the privacy of organization policies causes only a little delay in SDNs, which is completely justifiable by the privacy obtained.

中文翻译：

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通过安全的多方计算保护软件定义网络策略的隐私

在软件定义网络 (SDN) 中，控制器是从交换机收集的网络拓扑等信息的接收器。组织通常喜欢保护其内部网络拓扑并将其网络策略保密。我们借用安全多方计算 (SMC) 的技术来保护 SDN 控制器有关路由器状态的策略的隐私。另一方面，控制器的数量是 SDN 中 SMC 应用程序可扩展性的最重要问题之一。为了解决这个问题，我们制定了一个优化问题来最小化 SDN 控制器的数量，同时考虑它们在 SMC 操作中的可靠性。我们使用非支配排序遗传算法 II (NSGA-II) 来确定控制器的最佳数量，并使用此数量的控制器模拟典型 SDN 的 SMC。