In order to examine the best future solutions for convergence of Wi-Fi and 5G, this paper examines the current Wi-Fi interworking solutions available for 4G systems using either trusted or untrusted Wi-Fi access, through either Core Network based or RAN level integration. It also reviews the 3GPP 5G system approach to Wi-Fi access, which includes integration of untrusted Wi-Fi access in Release 15 and the new opportunities in Release 16 for trusted Wi-Fi access as well as wireline and cable modem access such as from a residential gateway. Release 16 specified Access Traffic Steering, Switching and Splitting (ATSSS) functionality is analyzed which enables data session over one or more concurrent accesses.

The first objective of this white paper is to explore the potential technologies that could help improve the performance of local connectivity at home.
In addition to this, the second objective is to look for solutions of radio resources management at home that would be controlled by the network. The current situation is that the local connectivity is selected by a connectivity manager embedded in the operating system of smartphones that may not have a complete view of what happens, for instance in terms of traffic on cellular networks.
The global objective for operators is then to keep home users connected wirelessly to their local – fixed access network based – connectivity (delivered e.g. by Wi-Fi, a “small cell at home”) with a “premium” quality of service instead of adding pressure on the Radio Access part of the mobile macro network. Challenges for mobile macro networks are for example a lack of (licensed) spectrum that can cover efficiently indoors from outdoor macro network (e.g. low bands spectrum), cost of the radio sites, incl. equipment.