Research on N4 Interface Decoupling Test

Due to the fact that the interface N4 between UPF and SMF has not been fully opened up yet, UPF and SMF must be bound by the same telecommunications equipment manufacturer. This greatly restricts 5G's ability to respond to customer demands. In order to meet the requirements of rapid deployment of edge UPFs in 5G network service vertical industry scenarios, The paper is introduced the decoupling test work of N4 interfaces for SMFs and UPFs of mainstream different telecommunications equipment. Firstly, the protocol and flow of 5G core network and N4 interfaces involved in the test are introduced, and then the N4 decoupling test carried out in the lab is elaborated, including the test environment, test cases and problems encountered in the test. According to the test results, it has been demonstrated that the research scheme has realized the function of service logic adaptation, which truly decouples the SMF and UPF from different equipment.