In this project, Geewell mainly walked through a design point of SDN to build a flexible VxLAN-based architecture for customers to deliver a core clearing platform that flexibly helps expand the capacity according to real load and speed up switching between servers and backups when disaster happening. The platform is included:  DMZ, interconnected with external networks for flow cleaning; external user management partition, interconnected with other cooperative clearing institutions; backbone partition, directly connected to the foreign headquarters; and the internal control partition and its associated monitoring area that carry on actual clearing business. 

These partitions are separated by border firewalls, in which every one based on flat architecture of SDN and backbone switches, distributes computing nodes to the leaf-spine switches, achieving flexible and controllable resource optimization under the premise of security.