During the Wi-Fi Offload Summit in Frankfurt on Jan. 23, a number of interesting developments in the Wi-Fi space were presented. A key question for mobile operators is whether Wi-Fi offload reduces the growth in mobile broadband (HSPA and LTE) traffic and thus the need for more mobile spectrum.
Research presented by Deutsche Telecom from tests in Hamburg and Rotterdam showed that when Wi-Fi is advertised and available free of charge in a particular area, this immediately generates substantial Wi-Fi traffic but does not reduce the volume of mobile data traffic. Towerstream Inc. presented conflicting evidence from its outdoor Wi-Fi offload network in New York.
From other findings presented, it is clear that both Wi-Fi and LTE traffic are increasing dramatically. Perhaps what is at work here is the Jevons paradox, which proposes that as technology progresses, the increase in efficiency with which a resource is used tends to increase (rather than decrease) the rate of consumption of that resource. The increasing availability of free Wi-Fi coupled with a rapid uptake of smartphones and cheap tablets would underpin this theory as one feeds off the other.
The growth in Wi-Fi is also driven by the desire of shops and malls to engage with shoppers on their in-store Wi-Fi networks. There is marketing value for retailers to have shoppers on their Wi-Fi network as soon as the shopper walks into the store. EE in the U.K. is turning this into a small business line, equipping supermarkets such as ASDA with a Wi-Fi infrastructure. Rather than identifying shoppers at the checkout when they swipe their loyalty card, ASDA hopes to be able to identify and engage with shoppers from the minute they are within the store’s Wi-Fi coverage. For example, coupons could be sent to a handset at the beginning of the shopping trip and can be used right away rather than languishing at the bottom of a shopping bag. This is just one of the many marketing benefits of free in-store Wi-Fi.
The simultaneous growth in Wi-Fi and LTE traffic may also be explained by the fact that Wi-Fi has other uses compared to cellular. The proliferation of TV Anywhere apps turns tablets and laptops into TV outlets, and in Canada, Bell has launched the first wireless TV proposition. TV over Wi-Fi creates a surge of Wi-Fi traffic in residential areas. Other devices in offices, public indoor spaces and outdoors rely increasingly on Wi-Fi connectivity because it is cheaper and more flexible than cable connections. This all takes Wi-Fi capacity in cities and raises the Wi-Fi noise floor.
In regard to the rapid adoption of tablets, all are Wi-Fi-enabled, but few are 3G (HSPA) or LTE-enabled. As people take these tablets out of their homes they will look for Wi-Fi access, thus increasing Wi-Fi hotspot usage. However, smartphones have a personal hotspot feature and where tablets are not in Wi-Fi coverage, we are seeing “cellular on-loading” from Wi-Fi devices.
Having paid for a shiny new LTE device, some customers would prefer to pay another €10-20 a month rather than having to faff about with logging onto Wi-Fi. Asking smartphone users to choose between LTE and Wi-Fi is the antithesis of a ubiquitous mobile broadband experience. However, Wi-Fi 2.0 with SIM-based authentication increases the ease of Wi-Fi access and may even be transparent to the user.
Another factor which determines the amount of LTE vs. Wi-Fi traffic are the policies for applications set in smartphones. For example, which bearer is allowed or preferred for which application. Some apps do not work via LTE; for example. FaceTime on the iPhone. In the U.S., the first version of the iPhone 5 with iOS 6 did allow FaceTime over LTE. This came as a bit of a shock to cellular operators as AT&T blocked FaceTime over cellular on most plans, but subsequently changed the policy. What cellular operators really want is to be able to set policies dynamically based on the app, the location, time of day and perhaps even the type of customer.
Nevertheless, most mobile operators have some Wi-Fi offload strategy. The focus is not so much on relieving congestion in busy areas but to deliver an “always best connected” value proposition. In short, LTE and Wi-Fi complement each other. The growth in Wi-Fi does not reduce the need for more cellular spectrum to serve the growth in mobile broadband traffic.
Written by Stefan Zehle, CEO Coleago Consulting