Politics, it’s often said, makes strange bedfellows. It turns out that spectrum does too. An unusual coalition that includes Comcast and other cable companies, consumer advocacy groups, and Google is facing off against T-Mobile and other cellular carriers.
At stake, the combatants say, is the future of Wi-Fi. An effort by the carriers to use unregulated portions of the spectrum to offload cellular traffic that’s clogging their networks could interfere with Wi-Fi, Bluetooth, and devices connected to the Internet of things, say the consumer groups and their allies in the cable industry. The carriers, they charge, would rather sell their cellular data, so putting the squeeze on free Wi-Fi is in their economic interest.
Nonsense, respond the carriers. “Wi-Fi is central to our customer experience, so co-existence is core to our desire to protect our customers’ Wi-Fi experience,” a T-Mobile exec tells me. (He asks that I not use his name.) One reason: T-Mobile’s network handles approximately 11 million Wi-Fi calls a day, he adds, so it needs Wi-Fi networks to be reliable.
Although the issue is pretty technical, involving technologies most people haven’t heard of, there’s already been some overheated coverage, such as in this Network World article: "LTE-U is coming to take your Wi-Fi away, consumer advocates warn." Even worse, lobbyists on the cable side have gotten the techno-simpletons in the U.S. Senate involved and are trying to get the FCC to step in.
I suspect the issue will be resolved by engineers on both side without serious damage to anyone. It does, though, highlight the increasing convergence of broadband, cable, satellite, and wireless business interests.
What's behind the LTE-U dispute
To address poor in-home cellular coverage, T-Mobile several years ago pioneered using the Wi-Fi network you're currently signed into to offload phone calls, a capability now used by all the major U.S. carriers on compatible smartphones such as the Apple iPhone 6 and Samsung Galaxy S6.
But offloading calls is different than what the carriers want to do with the unlicensed (that is, freely available) Wi-Fi and Bluetooth spectrum that has the cable companies and their allies so upset.
Modern smartphones use 4G LTE radio technology, and LTE runs on spectrum licensed by the FCC. That spectrum is filling up. Buying more spectrum is very expensive when it's even available.
That's why the carriers -- led by T-Mobile -- now want to use a version of the LTE cellular radio technology called LTE-U (the "U" stands for "unlicensed") that moves data and voice traffic normally carried in licensed parts of the spectrum reserved for cellular devices into the unlicensed frequencies that Wi-Fi and Bluetooth devices use.
There’s lot of room in the unlicensed bands, but it isn’t limitless. Your Wi-Fi network router wouldn't see the LTE-U device on the network; all your Wi-Fi network router might notice is that there's suddenly less spectrum available for it to use. “There’s real potential for interference,” says Chris Lewis, vice president for government affairs of consumer advocacy group Public Knowledge.
It’s no secret that the exponential growth of wireless traffic has put all of the carriers in a bind. Nor is it a secret that T-Mobile’s cellular network is weak outside of major metro areas, although the carrier disputes that claim. It makes sense that the “uncarrier” has been leading the charge to implement LTE-U.
Poor cellular coverage and saturated cellular towers are why the carriers encourage customers to connect via Wi-Fi whenever possible. Because Wi-Fi usage doesn’t count against a user’s data bucket, customers come out ahead. That’s why consumer advocates are so sensitive to anything that could make Wi-Fi harder to use.
Lewis notes that high-bandwidth uses of Wi-Fi, particularly video and VoIP, are the most susceptible to latency caused by interference. If video or voice calls get choppy, users would likely jump onto LTE, which they have to pay for. “The carriers have some incentive to push them there,” he says.
Such fears pushed four consumer advocacy groups -- Public Knowledge, Free Press, Common Cause, and the Open Technology Institute -- to lobby the FCC to prohibit or restrict the use of LTE-U. “Carriers also have powerful incentives to use LTE-U to deter mobile market entry by ‘Wi-Fi First’ providers, such as [traditional Internet service providers: the cable companies and landline phone companies]. Carriers deploying LTE-U will have the apparent option to adjust their access points to introduce just enough latency to frustrate consumer use of real-time applications, such as video calling,” they wrote in a filing to the FCC.
Tech companies concur with the consumer advocates. The FCC filing cites studies by Google, Broadcom, and others that claim that LTE-U can severely degrade Wi-Fi throughput, speeds, and latency (time delay) of packet delivery for real-time applications such as VoIP.
T-Mobile says the tests are flawed: “Claims by LTE-U opponents, particularly cable companies, that the technology will adversely impact Wi-Fi operations are based on testing with parameters set at extremes that do not represent realistic deployments or do not reflect actual LTE-U specifications,” Steve Sharkey, the carrier’s director of engineering, told the FCC.
If you’re wondering why Comcast and other cable operators care about this, the answer is simple: broadband and wireless increasingly go together. Comcast has more broadband customers than pay-TV customers, and anyone with a cable modem can (and usually does) use it with a Wi-Fi router.
Time Warner Cable is touting its Wi-Fi hotspots, and Cablevision is now in the wireless phone business with a Wi-Fi-only calling service dubbed Freewheel. Google, of course, has become an Internet service provide with its Google Fi high-speed fiber offerings.
Despite the saber-rattling, there's no need to panic
Notwithstanding the rhetoric and the different conclusions they've reached, I’d be surprised if the LTE-U issue doesn’t get resolved.
Although he’s wary, Public Knowledge's Lewis says, “We don’t oppose LTE-U; we just want it to work.” The T-Mobile exec I spoke to at some length was very careful not to sound hostile or overly combative toward the concerns of the consumer advocacy groups.
Furthermore, T-Mobile argues that its version of LTE-U will include technology called Listen Before Talk (LBT) that acts like a traffic cop. LBT makes the network aware of traffic, and it is designed to keep Wi-Fi and LTE-U signals separate to avoid interference. User traffic would be handed from Wi-Fi to LTE-U in a (hopefully) seamless procedure.
T-Mobile also maintains that although Wi-Fi is common in many cities' public areas, it is hardly ubiquitous, particularly in rural and suburban areas. T-Mobile envisions a user traveling in areas where there is no Wi-Fi and connecting to the Internet using LTE-U. If there’s no Wi-Fi, there’s no interference, the company argues.
Getting the free use of spectrum outside its core areas would be a big win for T-Mobile, which has been stung by claims that its coverage is still too limited to compete with offerings from Verizon and AT&T.
However this dispute turns out, we will see more and more confrontations and a reshuffling of the industry deck as the walls between once-separate technologies and business models crumble. Ultimately, all these companies are in the business of transmitting data, and it matters less and less where that data originates, over what spectrum it rides, or what information it contains.