The Voice Revolution

Samsung Galaxy S6 Edge with WiFi Calling Image Credit: Samsung

Phone makers are driving Mobile Operators' new services, and that is certainly the case for VoLTE and WiFi Calling. The increasing number of smartphones featuring VoLTE and WiFi Calling capabilities, according to Strategy Analytics Wireless Operator Strategies service report, has become a major force accelerating the take-up on these services across countries where they are rolled out.

For those who find the myriad of voice services offered by Mobile Operators a little overwhelming, it will be interesting to note that the mainstay of mobile business is currently undergoing significant changes. Much of the change has been brewing in the background for years now, with technologies such as VoIP introduced long ago to tap on the ability of Internet to transport voice from one computer to another, which gave rise to a large number of VoIP services, some of which, such as Skype, have become a major household service world over. Over-the-Top(OTT) applications were quick to capitalize on the trend towards the Internet and apps-based communications, and this in turn saw the meteoric rise of chat and voice applications such as WhatsApp, Viber and WeChat. 

These developments saw a huge chunk of Mobile Operators' voice and messaging revenues going to these apps, and this trend combined with the impending threat of commoditization and narrowing margins led to Mobile Operators introducing newer and more innovative voice and messaging services that are able to compete with those offered on VoIP and OTT. Enabled by the IMS infrastructure within the 4G LTE architecture, Mobile Operators turned on the Voice-over-LTE(VoLTE) service, the voice service on LTE, already rolled out commercially by more than 16 Mobile Operators in 7 countries, including the most recent rollouts by Vodafone PortugalBatelco of Bahrain and Three of UK (check out all other recent deployments of VoLTE here).

Infact, VoLTE is gaining such strong foothold that Mobile Operators have become busy signing roaming partnerships for the service, the latest involving NTT Docomo and LG Uplus. The VoLTE service replaces 3G voice for subscribers who are on 4G, removing the need for them to move back and forth between 4G and 3G when they are making calls and accessing the Internet simultaneously, and allows users to make calls using the phone's native dialer and contact list, without the need for an app, a new number or profile, as what is required for apps-based communication. Mobile Operators are placing a huge bet on VoLTE, and according to Juniper Research, Operator revenues from VoLTE are expected to reach US$100 billion by 2020.

The rise of VoLTE created a strong push for the introduction of WiFi Calling, which complements VoLTE perfectly, technology-wise, in areas where signal strengths are weaker, for example inside buildings and in areas such as parking lots. Again, the IMS infrastructure catalyzed the development of WiFi Calling service, and with the ability to switch-over from VoLTE to Wi-Fi and vice versa seamlessly, and with the availability of convergent billing solutions that make charging and billing of VoLTE-WiFi combined calls simple and hassle-free for Mobile Operators, a handful of Mobile Operators have moved ahead to roll out the service in the marketplace, with recent ones including AT&T, Cell C of South AfricaVodafone UK and Swisscom.(Full list of recent deployments of WiFi Calling is found here). 

Wi-Fi Calling

Against this background, the generosity of phone manufacturers in building in VoLTE and WiFi Calling capabilities across their new smartphone models has sparked interest among owners of these devices to give both services a try, resulting in increased sign-ups. And why wouldn't they? It means that subscribers pay the same voice rates for HD voice quality, and have an omnipresent service throughout the day as they move in and out of LTE, WiFi and 3G zones. It also means that Mobile Operators can start monetizing their LTE and WiFi investments, and is perhaps why some Operators such as EE of UK included 4G + and WiFi calling capabilities when it launched its own brand smartphones.

For subscribers, VoLTE and WiFi Calling also open up access to new attractive packages such as WiFi-only plans that allow them to make calls in WiFi zones to anyone's mobile device while surfing the Internet for free where open WiFi is available. The same applies for WiFi-only roaming plans that allow subscribers to call back home from their hotels and airports, and use data across various WiFi hotspots without incurring huge usage bills typically paid on normal roaming plans. As technology is further enhanced, for example, the extension of WiFi Calling capabilities to WiFi-only devices as announced by Ericsson recently, which means that devices without a SIM can actually be used to make calls using Mobile Operator's Voice-over-WiFi services, these new voice services will provide more users with more channels to communicate as and when and how they wish on various plans that suit their budgets, device types and network coverage.  

Catching up on this revolutionary path is the good old messaging (SMS) service, that, under the Rich Communications Services banner is also transforming rapidly to offer an enhanced suite of messaging and related services on 4G LTE, enabling SMS to take on the competition from its OTT counterparts. RCS, also based on IMS and provided natively on the mobile phone, is a service that goes beyond messaging to allowing file transfers, screen sharing, emoticons, enhanced phone book, group messaging and location sharing, among others. RCS will thus complete the Mobile Operators' portfolio of next-generation communication service offerings, delivered on a single data connection.   

Interestingly too, Mobile Operators are also looking into capitalizing the growth in the VoIP market, namely the developments in the WebRTC (Web Real-time Communications) area, specifically for enterprise clients. WebRTC service rolled out via Mobile Operators' own WebRTC platform allows closed communications between specific user groups covering voice, messaging and video. AT&T in January this year announced commercial support for WebRTC via its enhanced WebRTC APIs. The enhancements extend WebRTC to landlines and mobile phones, not just P2P or browser-to-browser sessions.

Over the next year, Mobile Operator's voice and messaging services will continue to transform, adapting to the emergence of newer communication needs, including those required for the Internet-of-Things (IoT), for enterprises that are becoming increasingly mobile and for digital consumers who are becoming increasingly dependent on more than a single device, who are opting for more flexible plans and who demand higher service experience at all times.

Mobile voice and messaging will thus continue to be the pillars of Mobile Operators' business. Infact, in some circumstances, mobile voice and messaging can even 'take over' fixed voice connectivity, as in the case of South African Operator, Telkom, which last week introduced the 'Fixed-Line-Look-Alike (FLLA)' service that attempts to create a fixed phone experience using cellular powered devices to tackle the need for a highly reliable and consistent service for more than 390,000 of its 'fixed-line' subscribers! Such is the power of mobile. 

Executive Editor of The Fast Mode | 5G | IoT/M2M | Telecom Strategy | Mobile Data Innovations 

Tara Neal covers stories on strategies and initiatives in the Digital Telco space, and anchors the 5G and IoT/M2M verticals on the publication. Tara holds a First Class Honours in BSc Accounting and Finance from The London School of Economics, UK and is a CFA charterholder from the CFA Institute, United States. Tara has over 20 years experience in technology and business strategy.

Follow her on Twitter @taraneal11, LinkedIn @taraneal11, Facebook or email her at


Three Ireland Moves Customer Care Calls to Limerick from Mumbai


Innovation via BSS – Making it Possible for MVNOs and Enterprises to be Niche, Agile and Profitable

Latest Videos



Artelligence 2019

Network Virtualization and SDN Asia

Network Virtualization & SDN Americas

Mobile 360 Digital Societies 2019

TADSummit 2019

MWC Los Angeles 2019

The Digitrans Forum 2019

Mobile 360 Eurasia 2019