Design and Implementation of a 5G Network Architecture Based on Software Defined Network

The 5G network supports a variety of radio access technologies RAT to access the core network, but each radio access technology has its own control entity, and each control entity has different control strategies, which leads to a high degree of control fragmentation and suboptimal utilization of network resources. EPC does not support centralized management of RAT, so it is necessary to define additional network elements to realize centralized RAT control strategy. Although the new 3GPP 5G standard provides support for unified core, the access decision at RAN level of radio access network is still made by different RAT control entities. In view of this phenomenon, this paper plans to use SDN paradigm to reconstruct the RAN level of radio access network and 5GC of 5G core network on the basis of 3GPP 5G network architecture, and concentrate the control authority of all RATs into the RAT unified control core based on AMF network function to realize centralized management of different radio access technologies. Based on this new architecture, centralized RAT control strategy can be constructed, thus reducing the fragmentation of network control and finally realizing the rational utilization of network resources. This paper compares the signaling load between the new architecture and 3GPP 5G architecture, and analyzes the influence of the introduction of SDN paradigm on the frame delay.