VoLTE is powered by the IP Multimedia Subsystem framework, the implementation of which also allows operators to roll out over-the-top services such as instant messaging based in turn on a specification called Rich Communication Suite (RCS).
Work on the suite started in 2008, and the goal was to turn IMS into standardized services for operators. IMS had been around for a long time, but due to the framework's complexity it hadn't taken off, a situation which RCS was meant to change.
Even though it is off to a slow start, there is a lot of hope in the telecom industry that RCS will help operators develop more attractive offerings and compete with Web-based services, while at the same time potentially delaying the arrival of VoLTE.
"In the past month or so, bundling voice and messaging has become a priority for operators, and that is having somewhat of a delaying effect," said DePuy.
The combination of VoLTE and RCS will allow users to communicate in new ways, according to Warren. The vision is that they will be able to see who is available, and chat, share files across any device, on any network, with anyone in their address book.
"What I think will be really interesting is the step beyond that when operators expose those capabilities to application developers," said Warren.
But even if VoLTE works well, it won't take off until there are a number of great smartphones for users to choose between, including a future version of Apple's iPhone.
"Handsets will be shipping in small volumes initially, and that is not good for keeping prices low," said DePuy.
TeliaSonera's motivation to implement VoLTE isn't helped by the fact that Europe is behind the U.S. when it comes to rolling out 4G. That has resulted in fewer smartphones and tablets being adapted for the European spectrum bands.
The launches in South Korea and the U.S. are backed by LG Electronics and Samsung Electronics, with smartphones like the Galaxy S III available. It is good news that Samsung is onboard, according to Warren. But when it comes to Apple he isn't as hopeful.
"When it comes to this kind of technological evolution, Apple isn't on the bleeding edge. Instead it is relatively cautious," said Warren.
Together Samsung and Apple own the smartphone market with a 50% market share, according to IDC.
Still, the arrival of the first VoLTE services is a really positive step for 4G as a whole, and shows that LTE can become the preeminent technology for all services, according to Warren.
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