POSEIDON: A Consolidated Virtual Network Controller that Manages Millions of Tenants via Config Tree

As the cloud rapidly expands in scale, the virtual network controller must manage an increasing number of devices with higher update frequencies. Furthermore, the emergence of cloud-native services has substantially intensified programtriggered updates, leading to more frequent API invocations. To enhance performance and extensibility, we propose POSEI-DON, a novel virtual network control framework. Specifically, to reduce operational expenses (OpEx), we have consolidated the common functions of multiple service controllers into a single controller. To manage heterogeneous devices and eliminate the multi-table lookup complexity due to config dependencies, we introduce Trident, a tree-based service-and device-independent abstraction, so that config dependency calculation can be replaced by more efficient tree traversal. After deploying POSEIDON on Alibaba Cloud, we observed a 21x increase in the throughput of virtual network configuration tasks, along with a 4.4x decrease in the P99 API processing latency. POSEIDON completes the task of enabling hundreds of Elastic IP addresses (EIPs) 1.8 to 55 times faster than Vendors A and B, both of which are among the top 5 providers [6], for identical network configuration jobs.

In this section, we present the virtual network configuration workflow and discuss the challenges encountered during years of production deployment of our virtual network controller.