5G standalone (SA) and non-standalone (NSA)
Updated
5G standalone is a 5G network with its own 5G core; 5G non-standalone adds 5G radio to a 4G network and keeps the 4G core, with an LTE cell acting as anchor. Non-standalone relies on the dual connectivity between LTE and NR specified in 3GPP TS 37.340.
In practice
Network slicing and RedCap need a standalone network. Many operators still run non-standalone 5G, so an IoT device that depends on 5G features must be tested on each target network.