US Patent 11792227 I2NSF network security function facing interface YANG data model

The present disclosure provides a system and method of providing a security service by means of a network operator management system in a security management system, the method including receiving a high-level first security policy from an I2NSF (interface to Network Security Functions) user; receiving an available security service from a developer's management system; creating a low-level second security policy corresponding to the first security policy on the basis of the security service; and transmitting a packet including the second security policy for setting the created second security policy to each of a plurality of NSFs (Network Security Function) to an NSF instance, wherein the network operator management system and the NSFs are respectively connect to an I2NSF NSF-laving interface, and the second security policy includes at least one or more of 1) blocking SNS access during business hours, 2) blocking a malicious VoIP (Voice over Internet Protocol) or a malicious VoCN (Voice over Cellular Network) packet, or 3) mitigating flood of http and https for a company web server.