Voice over LTE (VoLTE) is considered by many to be revolutionary both for mobile operators and for subscribers. Operators, once they have established their VoLTE networks, will no longer have to maintain separate networks for voice (circuit-switched) and data (packet-switched). This will save on operational and capital expenses. Subscribers who use VoLTE will be able to use high-quality voice and data applications simultaneously, and the clarity of their voice calls will improve.
So why has VoLTE taken longer than anticipated to deploy? The answer lies in several challenges, which I’d like to discuss briefly.
- The successful roll-out of HD voice and video calling services requires VoLTE technology to be simultaneously available in both the mobile network core and on mobile handsets. Most mobile operators’ core infrastructures are not fully equipped to simultaneously support circuit-switched and packet voice. In addition, VoLTE-enabled handsets are not yet widely available.
- VoLTE promises to move wireless calls from the legacy circuit-switched network to the all-IP-based LTE network. The formidable task of supporting both switched-circuit and packet-based technologies, however, is not economical for mobile operators in markets where LTE is not yet deployed. What’s more, mobile operators are still resolving VoLTE call interoperability issues to support customers who are roaming.
- Finally, successful VoLTE deployment depends heavily on nationwide LTE deployment and the adoption of LTE-based small cells for in-building voice enhancements. Adoption of LTE-based small cells for residential and enterprise applications is still very low.
Despite these challenges, numerous efforts are underway to realize the promise of VoLTE. To expedite nationwide rollout, several leading mobile operators have begun limited trials in major markets, testing voice quality and equipment interoperability. Suppliers are slowly rolling out VoLTE-enabled handsets; and a consortium of mobile operators is negotiating roaming agreements for smooth inter-network transitions. The potential long-term benefits of VoLTE to operators and consumers alike are too great to miss and they easily outweigh any temporary intermediate setbacks.