Giving LTE a Voice

Five Ways to Prepare Your Network for the Onslaught of Faster Wi-Fi Devices

The emergence of LTE means that subscribers are receiving faster speeds for their mobile devices, but it also means that something has to be done about voice services.

The reason is that the first LTE platforms don’t touch voice services. Folks making old-fashioned person-to-person calls were switched back to 3G networks, and that’s an inefficient use of bandwidth.

Enter Voice Over LTE (VoLTE), the technology that brings voice into the new platform. The technology is rolling out; however, it is very much a work in progress. One big challenge is that a VoLTE platform deployed by one carrier is not necessarily interoperable with that from another. Unless that issue is resolved, VoLTE essentially is a non-starter.

This week, Verizon and AT&T said that they are working to make their VoLTE systems interoperable next year. With the two top players working together, it seems likely that the industry will follow.

But they’d better figure it out, and quickly. Newfield Wireless has detected a significant increase in VoLTE traffic since the introduction of Apple’s iPhone 6 and iPhone 6 Plus:

The majority of voice calls made on other 4G-enabled devices are currently routed through legacy 2G and 3G networks, due to the fact that not all networks and devices are optimised to deliver next-generation voice services. iPhone 6 devices are VoLTE-compatible and as a result, U.S. networks have experienced a surge in VoLTE calls since the September launch.

There is more to think about on the advanced voice front, however. Iain Gillott, iGR founder, posted to RCR Wireless News a very interesting analysis of the relationship between VoLTE and voice over WiFi (VoWiFi), an approach to advanced voice services that he suggests makes more sense in some instances.

The core of the issue is that VoLTE is subject to the same coverage shortcomings as other cellular services. These problems are exacerbated in homes and have become especially problematic for the increasing percentage of people who have given up their landlines.

In the 3G world, Gillott writes, the coverage problem was addressed by deploying femtocells or line extenders in the home.

There is another option, though. The explosion of Wi-Fi means that VoWiFi is a viable approach to providing voice services to LTE subscribers. Gillott points out that new smartphones often support this service. T-Mobile, he writes, already passes voice traffic between the two platforms.

The approach has its plusses and minuses. The carrier saves money since no additional hardware is required. It’s a quick fix: The solution already is in most people’s homes. However, since the Wi-Fi infrastructure belongs to the subscriber, the carrier loses control over how it is managed and how well it works. The subscriber will continue to call, though, when service isn’t up to par.

The bottom line to Gillott is that VoWiFi is not a panacea, but can be a powerful tool for mobile operators:

How this all works out will be interesting to see. VoWiFi is likely to play some role in the indoor VoLTE service architecture but may not be for everyone. LTE femtocells may still be deployed but in fewer numbers than the 3G versions and in more select environments.

Either way, there are solutions to the issue of getting VoLTE indoors; it is just a matter of the ‘who, what, where and how.’

It is imperative that a solution for voice on LTE be rolled out quickly, as the LTE technology takes over across the U.S.

Carl Weinschenk covers telecom for IT Business Edge. He writes about wireless technology, disaster recovery/business continuity, cellular services, the Internet of Things, machine-to-machine communications and other emerging technologies and platforms. He also covers net neutrality and related regulatory issues. Weinschenk has written about the phone companies, cable operators and related companies for decades and is senior editor of Broadband Technology Report. He can be reached at cweinsch@optonline.net and via twitter at @DailyMusicBrk.