LISBON, Portugal -- Three UK said its new voice over LTE (VoLTE) service has run into several issues including accidental roaming by customers onto other operators' networks.
Speaking at the WeDo Technologies' Worldwide User Group and Summit, here, Stuart Waton, revenue assurance team leader at Three UK, said the operator's '4G Super-Voice' VoLTE service, which launched in September 2015, has randomly allowed users to roam onto other networks and so caused financial loss for Three.
Waton explained that a quirk of VoLTE interconnection has enabled Three VoLTE customers to roam onto other networks, which have counted calls made by the operator's subscribers as a data call.
"We didn't know this could happen," he said.
Waton said the outcome was a loss of revenue for Three UK. For example, one subscriber who placed a VoLTE call while visiting the Caribbean should have paid £16 (€20.31/$23.06) for a call back to the UK. Because of the quirk, the user actually paid in the region of £0.03.
Three UK raced to launch its VoLTE product before its competitors, hoping to cash in on the advantage the technology brings: better indoor coverage for end users. In that regard, the service has proven a success, Waton said, explaining that VoLTE "is addressing the historical issues our customers have had; it makes a real difference to our customer base."
The service currently covers 65 per cent of the UK population, with the rollout continuing throughout 2016.
Waton noted that a lack of compatible handsets remains an issue for the operator's VoLTE service, and has hindered take-up.
"We have had some issues with the adoption of the 4G service; at the moment it is limited to handsets that have received an upgrade. The list is being expanded, but it does make an issue," he said.
He added that the problem is further complicated by the fact that only devices purchased by consumers directly from Three UK can be upgraded. Waton explained that the operator ended up releasing compatible iPhones later than expected because of Apple's strict rules on what changes can be made to its devices.
Waton noted that around 0.08 per cent of calls made through its network in the UK are now VoLTE. "That doesn't sound like much, but that's one out of every 125," he said.
Because it uses Three's low-frequency 800 MHz spectrum, the VoLTE service allows a mobile signal to travel much further into buildings and extends its reach to more rural areas.
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