Vodafone will launch Wi-Fi Calling and Voice over 4G (VoLTE) this summer.
Both services require handsets that support the technologies, and Vodafone is keeping mum as to which ones it will be shipping.
Wi-Fi Calling is a UMA (Unlicensed Mobile Access) service and for certain high-end handsets is an alternative to using the Vodafone SureSignal femtocell. It saves on the cost of having dedicated hardware, managing and configuring it.
In parallel, Vodafone will also be launching Voice over LTE (VoLTE). When the standards for 4G were defined they “forgot” about voice. VoLTE is the IP service which adds voice to 4G mobile calls.
Both services are IP-based, so you can move between VoLTE and Wi-Fi calling andthere is circuit-switched fallback for VoLTE but not for Wi-Fi calling.
So if you have VoLTE outside your house, you can move seamlessly between outdoor and indoor Wi-Fi. Yet if you live in a 2G/3G only area, you will drop calls when leaving home if they were started on Wi-Fi. You will drop calls when arriving home if outdoor coverage is 2G/3G as you move indoors and out of that coverage, even if you have Wi-Fi.
Falling up from 2G/3G to VoLTE will not always work.
The Reg recently tried Vodafone’s VoLTE service at its labs in Newbury and we were impressed with the sound quality – albeit standing in an exceptionally quiet lab – and particularly impressed with the low latency.
Jeroen Hoencamp, Vodafone UK's chief executive, said: “Our Wi-Fi Calling service will ensure that our customers never miss a call. It is another important step towards our commitment to build the UK’s strongest converged network.”
EE has had UMA for some time, and O2 offers TuGo, which is app-based VoIP, but Vodafone is the first UK network to take the brave step into VoLTE.
Wi-Fi calling opens up the ability to say “I’m on the train” to London tube travellers - well, to those who are in stations. As ever, you’ll be incommunicado in tunnels. ®