WiFi Calling

fon wifi talk

Offer a better connectivity experience by enabling voice over WiFi networks (VoWiFi)


WiFi Calling facilitates calls and texts over WiFi when cellular coverage is poor or nonexistent, without the need for high mobile network and frequency license investments.


VoWiFi enables telco operators to deliver an “always best connected experience” to customers who will be able to make and receive calls and text messages wherever there is a WiFi connection, regardless of quality of 3G/4G coverage. Providing seamless connectivity, WiFi Calling makes life easier for your customers who no longer need to use VoIP OTT apps.


A worry-free roaming enabler for your customers, with WiFi Calling they can stay connected everywhere without the fear bill shock. Traditionally, exaggerated roaming charges have shaped the behaviour of travellers, who have often simply turned off their phones or relied on OTT apps. Offer a roam-like-at-home proposition with your own value-added services, and reduce third party intervention.

CSP benefits

Enhanced indoor and rural area coverage with lower investments compared to femtocell deployments

Enhanced customer experience and Net Promoter Score (NPS) – directly translates into churn reduction

Different tarification methods can be applied (like cellular)

CSPs regain control: OTT becomes less important to users

Large savings on roaming interconnection charges, enabling “roam like at home” plans

Increased revenue is WiFi Calling is priced as an additional service/included in premium plans

End user benefits

Increased reach: users can make and receive calls and texts without mobile coverage

Always-best-connected experience over available RANs

Seamless user experience: customers use their handset as usual (native dialler) without having to download OTT apps, create new accounts, or buy additional credit

Users avoid roaming call bill shock

User story

fon wifi talk

I have terrible cellular coverage at my workplace.

If I connect to the WiFi there, my data-centric services (WhatsApp, email) work just ne, but I can’t receive calls or texts, which is really annoying.

Fon wifi talk

I can use Skype or WhatsApp to make calls, but it’s not the same.

Fon Solutions wifi talk

WiFi Calling lets me receive and make calls and send texts over WiFi just as if I were using a mobile connection.

Key features

Fon’s Solution provides everything needed for WiFi-cellular call interworking. And With one of the world’s largest hotspot networks (20 million hotspots worldwide), Fon massively extends service availability for WiFi Calling.


Fon is getting onboard with industry players and assuming an untrusted approach for WiFi Calling. The name “untrusted” can be misleading, since security is always guaranteed through an IPSec/IKev2 tunnel session where voice and messaging data is encrypted along the communication path.

Carrier-grade connectivity and tight mobile core integration:

  • Multiple authentication mechanisms: EAP (SIM, TTLS,  AKA, AKA’), Open SSID (WISPr), external sources (Radius, LDAP, Active directory)
  • RADIUS accounting per session including time usage, volume usage, and lawful interception data. CDRs configurable per integration
  • Integration with mobile core systems

Advanced connection manager capabilities (app or SDK)

Enhanced quality of experience management

WiFi Calling architecture

Want to make the most of WiFi Calling?

Make sure you’re providing the QoS for an always-best-connected experience with our Connectivity Experience Solution


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use cases