Long Term Evolution over Wi-Fi represents one more way mobile and other service providers are combining licensed and non-licensed spectrum assets to underpin their businesses.
As planned, T-Mobile US will use 5-GHz Wi-Fi spectrum to complement its primary use of licensed 4G LTE spectrum, probably mostly in high-density areas, and primarily at peak hours of mobile usage in those areas.
LTE Advanced over Wi-Fi is seen as an approach well suited to small cells that mobile operators plan to deploy in high-density areas, primarily to support higher bandwidth in the downstream.
As mobile operators have learned to rely on offloading data demand to unmanaged Wi-Fi access, they also will be able, using LTE over Wi-Fi, to augment LTE operations based on use of licensed spectrum.
Other advantages include a more seamless end user experience, as users will not actively have to toggle back and forth between the mobile data network and local Wi-Fi. User experience also should be more consistent.
T-Mobile US is expected to add LTE over Wi-Fi as soon as 2015, a way of enhancing its LTE network bandwidth. You might call LTE Advanced over Wi-Fi an example of “Wi-Fi also,” a primary reliance on the mobile network, but augmented by managed Wi-Fi, compared to the way other service providers approach Wi-Fi.
France’s Free Mobile, U.S. mobile providers Republic Wireless and Scratch Wireless, for example, take an approach we might call “Wi-Fi first,” preferring that users connect to Wi-Fi as a first choice, then default to the mobile network only when Wi-fi is not available.
Eventually, firms such as Comcast are likely to follow that same approach when launching mobile service. Google also is said to have looked at the idea.
To be sure, whether public Wi-Fi can compete with mobile has been asked for a decade and a half. Until recently, the answer has been “not yet.” The question was asked of 3G networks and now is asked about 4G networks.
Arguably, two major hurdles will have to be overcome, first, ubiquity of public Wi-Fi access and second, the business model.
For the moment, ubiquity remains the biggest challenge, as it remains difficult to ensure coverage, let alone roaming, on public Wi-Fi today, outside the fairly limited universe of cafes, malls, hotels, airports and other areas where there is high pedestrian traffic.
So far, no service providers have been brave enough to try a “Wi-Fi-only” approach for mobile phone service. Also, virtually all mobile service providers now encourage use of unmanaged Wi-fi “sometimes” for Internet apps.
In other words, no service providers have tried to build a mobile service exclusively on untethered access (hotspot based). The “safest” model for a non-facilities-based provider is “Wi-Fi primary, mobile network secondary.”
T-Mobile US likely will be first in the U.S. market to implement an approach that might be called “mobile first, managed Wi-Fi second.”
In the future, there might be other possibilities. Content consumption already dominates real-time communications as a lead app for mobile and untethered devices. Many tablet owners find “Wi-Fi first” a quite acceptable connectivity choice.
As content consumption grows, on all devices, it is possible a new market niche could develop, even for “mobile phone” service.
One might argue such concepts have been tried before, as with the Personal Handy Phone System. There was some thinking such a service might also develop in the United States, around the time Personal Communications Service spectrum was awarded in the 1.8 GHz band.
As it turned out, PCS wound up being “cellular telephone service.” But all that was before the Internet, before broadband, before the rise of Internet-based content consumption.
It is hard to tell whether all those changes, plus the advent of smartphones and tablets, small cells and more public Wi-Fi, will finally enable a Wi-Fi-only approach to services that appeal to a large base of consumers.