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Traditional IP networks are difficult to manage, owing to their rapid expansion and dynamic changes. Software‐defined networks are introduced to simplify network management by separating the network control plane from the packet forwarding plane. Using one or several controllers, SDN switches can be configured to forward data packets to their destinations. The controller placement problem aims to determine the number of controllers and their locations to meet network service requirements. Early approaches used the k‐median and k‐center algorithms, which select k controllers to minimize propagation latency without considering network resilience. In this paper, we developed a new nodal metric, nodal disjoint path (NDP), which measures a node's importance in terms of its diverse connectivity to other nodes. Based on NDP, we propose two algorithms, NDP‐global and NDP‐cluster, for determining the …