Divided hierarchical network system based on software-defined networks

A divided hierarchical network system based on software-defined networks, the divided hierarchical network system comprising:

• a hardware processor;
• a memory comprising instructions executable by the hardware processor;
• and
• an edge controller executable by the hardware processor and configured to:
• generate forwarding information in response to a flow forwarding inquiry from a lower level and respond to the request with the forwarding information;
• generate mapping information such that each of a plurality of edge ports of each of a plurality of switches that form the lower level corresponds to each of a plurality of virtual ports of one virtual switch;
• if it is not possible to generate forwarding information in response to a request received from a lower level for forwarding a flow that comprises edge ports, query forwarding information to an upper level regarding a flow in which the edge port is converted into a corresponding virtual port based on the mapping information, wherein the plurality of switches that form the lower level form edge divided networks which are connected to each other, wherein:
• the lower level of a route controller that responds to the forwarding information regarding a flow of the upper level comprises a plurality of edge controllers;
• at least a first to a third edge controllers among the plurality of edge controllers form a loop-type topology;
• the route controller includes information of a plurality of equivalent topologies as many as a number of hops between all nodes based on a topology of all nodes that form a lower level of the first to third edge controllers;
• edge ports of the information of the plurality of equivalent topologies are converted into virtual edge ports mapped by the first to third edge controllers;
• and
• the route controller takes into consideration more information of the plurality of equivalent topologies than the loop-type topology of the first to third controllers when generating the forwarding information in response to an inquiry of flow forwarding information between the virtual edge ports.