Currently, the emergence of edge computing provides low-latency and high-efficiency computing for the Internet of Things (IoT). However, new architectures, protocols, and security technologies of edge computing need to be verified and evaluated before use. Since network emulation based on a cloud platform has advantages in scalability and fidelity, it can provide an effective network environment for verifying and evaluating new edge computing technologies. Therefore, we propose a high-performance emulation technology supporting the routing protocol based on a cloud platform. First, we take OpenStack as a basic network environment. To improve the performance and scalability of routing emulation, we then design the routing emulation architecture according to the software-defined network (SDN) and design the cluster scheduling mechanism. Finally, the design of the Open Shortest Path First (OSPF) protocol can support communication with physical routers. Through extensive experiments, we demonstrate that this technology not only can provide a realistic OSPF protocol but also has obvious advantages in the overhead and performance of routing nodes compared with those of other network emulation technologies. Furthermore, the realization of the controller cluster improves the scalability in the emulation scale.