Experimental Integration of Non-5G Capable Devices into 5G Networks via Untrusted WLAN: the UNIF Approach

This paper introduces the Untrusted Non-3GPPInterworking Function (UNIF), a novel network functiondesigned to enable devices that do not support the 5G NASprotocol over untrusted non-3GPP access networks to seamlesslyconnect to a 5G core network. Such devices are referred to asNon-5G Capable over Non-3GPP (N5CN3) devices. UNIF bridgesa significant gap in current 3GPP specifications by allowing suchdevices to utilize untrusted non-3GPP access networks, such aspublic WLANs, for 5G connectivity. The prototype implementationof UNIF supports single or dual Packet Data Unit (PDU)Sessions per N5CN3 device and dynamic traffic routing for edgeand remote data networks. Evaluation results show that UNIFachieves an average connection setup time of 284ms, downlinkthroughput of 552 Mbps, and low latency of 18–35 ms, validatingits potential to extend 5G to N5CN3 devices.