More WiFi/cellular convergence talk: will 5 be the G that finally cracks it?

• The  Wireless Broadband Alliance (WBA) and the Next Generation Mobile Networks (NGMN) Alliance have put their heads together to come up with a white paper
• It sets out the places where convergence would be a boon and what applications might be enabled
• But doubts (no doubt on both sides) remain

Another vigorous nod in the general direction of WiFi/5G convergence was launched this week via a joint white paper produced by the Wireless Broadband Alliance (WBA) and the Next Generation Mobile Networks (NGMN) Alliance, and authored by a joint task force. The effort isn’t about new standards but is more in the manner of a commercial push to highlight all the advantages to both sides, it claims, by bridging the various  technology gaps and getting both sets of radio technologies to play nice with each other. All it needs is a nudge here and there. 

And there are all sorts of advantages, especially for large telcos - such as BT and AT&T, for instance - who find themselves with feet planted firmly in both technology camps. 

According to the paper’s findings, near the top of the list is mobile operators being able to use the convergence of Wi-Fi and 5G to gain improved visibility into Wi-Fi networks enabling them to control the  ‘customer experience’ while, it’s maintained, Wi-Fi operators can benefit from improved visibility in the other direction for transition management as they operate overlapping cellular and Wi-Fi networks, ultimately resulting in an improved user experience.  

The paper naturally highlights business opportunities created through the convergence of Wi-Fi and 5G at the network and RAN layers, including enterprise use cases, manufacturing, public hotspots and residential applications. 

But in the long run the paper envisages new 5G use cases where the combined resources of both cellular and Wi-Fi networks can be made to work closely together to provide ‘cost-effective’ ways to meet diverse requirements. Things like throughput, latency, connection density, coverage, availability and reliability. In other words, mixing the quality and control capabilities of cellular with the vast cost advantages of Wi-Fi 6 (especially and soon to arrive) working in public and shared spectrum. An advantage which is really rammed home with the low cost of Wi-Fi connectivity in comparison to its 5G equivalent.

According to Kevin Holley NGMN Alliance spokesperson and BT’s Director of Technology Standards and Ecosystems, BT’s objective is to give “seamless connectivity to our users and hopefully keep upgrade costs (in the BT network) to a minimum.” One of the best ways of doing this is to have a core network capable of treating its various access networks in a transparent manner.  “We’re looking virtualising a lot of the core network. That’s the story you probably hear quite a lot of, but it’s very important.”  

According to Kevin, “Wi-Fi 6 brings extra capabilities because it has a scheduler, so it’s not just up to the device to say let’s go onto this Wi-Fi access point or that Wi-Fi access point.  The hub or access point can dictate where the device can go and that helps with things like prioritisation (if there is close convergence).

“If you have an enterprise network with Wi-Fi 6 you have a lot of control over that network to set security and priority for all the attached devices, but carriers can currently have no way of getting information on what’s going on with network-attached Wi-Fi via their core networks.

“So the opportunity here is to talk to the back-end of the Wi-Fi system from the intelligence in the core of 5G to have a sort of cross-fertilisation that can enable a more seamless experience for the customer.

 “The white paper is a bunch of ideas that says there is an opportunity here to make the most of both 5G and the in-home Wi-Fi environment so you (the user) can get the best of both worlds. Get the best connection wherever you happen to be, and for a corporate user: you gain control over device security. Our idea is to encourage the standards people to work towards this sort of support,” he says 

Kevin’s company, BT, “is kind of sat in the middle,” he says, with a considerable Wi-Fi heritage from its deployment of residential broadband amongst other things.  So how does he see the oft-mentioned technical rivalry/gulf between those schooled in telco technology and those who have come up through LANs and Wi-Fi? 

“It’s interesting. When we get into coordinated projects we see that people from both sides tend to work closely together to make the whole thing work,” he maintains. 

That augurs well for Wi-Fi/5G convergence within large service providers, but the same can’t be said for many Wi-Fi advocates who are wary of telcos bearing gifts. 

“It’s not really a sinister ’take over Wi-Fi’ plan’ says consultant and Wi-Fi advocate, Claus Hetting of Wi-Fi Now. “It’s just the usual attempt by carriers to incorporate Wi-Fi into some sort of service fabric.. so far, historically, those attempts haven’t ended well,” he maintains. 

“The challenge with this kind of convergence is less technical than it is commercial and it’s not clear to me who would commercially benefit, how, and from what.

“In the 4G era, the WBA was very interested in ‘4G/Wi-Fi convergence’ until 4G unlicensed radio (LTE-U) showed up, then they were suddenly more interested in that and ready to ditch Wi-Fi altogether. The 5G folks seem to think that replacing a 4 with a 5 opens up new markets - the truth is that it most often doesn’t because the underlying business case doesn’t really change.

“Now with 5G, this WBA/NGMN scheme is trying to gain access to a ‘cellular enterprise market’, but it’s not clear to me how enterprises would benefit. In my view, most enterprises will have little or zero interest in (typically much more costly) cellular solutions.”