5G-Flow: Flexible and Efficient 5G RAN Architecture Using OpenFlow

Convergence of multiple access technologies is one of the key enablers in providing a diverse set of services to the Fifth Generation (5G) users. Though the 3rd Generation Partnership Project (3GPP) 5G standard defines a common core supporting multiple Radio Access Technologies (RATs), Radio Access Network (RAN) level decisions are taken separately across individual RATs as the existing 5G architecture lacks a unified control and management framework for a multi-RAT network. A unified access network is likely to utilize RAN resources more efficiently and provide an improved performance. To bridge these gaps, we present an OpenFlow based RAN architecture comprising multiple RATs. We refer to it as \textit{5G-Flow}. With minimal changes in the 3GPP 5G RAN and none in the core network, we are able to realize a unified and integrated multi-access 5G-Flow RAN. We simplify the existing 3GPP 5G RAN by replacing RAN nodes with OpenFlow switches and a Software-Defined Networking (SDN) controller. Moreover, a UE in the 5G-Flow network can use 5G RAN to connect to any core network (4G or 5G) or directly connect to Internet without going via the core network. We also present a simple method to realize 5G non-standalone architecture using 5G-Flow RAN. We have developed an evaluation platform to compare the performance of our architecture with the standard 3GPP 5G network. Results demonstrate significant gains in the network performance of 5G-Flow RAN architecture over the existing 3GPP 5G network.