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Voice over X: Rising to the Next Challenge for Voice Services


In the beginning, there was only voice. Then along came the iPhone, which revolutionized the smartphone segment and gave way to the emergence of mobile data services.

Despite the growing importance of mobile data, which has transformed the way in which the world communicates, voice and SMS services are still a significant part of service providers’ revenue.

In fact, subscribers rank the quality and coverage of mobile voice/SMS services as their top criteria for choosing a mobile operator. And because the competition between mobile operators is intense, it is imperative that LTE operators provide subscribers with high-quality and reliable voice services.

To do so, operators have access to a variety of different technologies that can be deployed on their networks, including circuit-switched fallback (CSFB), which relies on legacy networks to deliver voice services to LTE. However, relying on 2G/3G networks to provide voice services is not a sustainable solution going forward due to the technical challenges involved and operators’ objective to free that spectrum and reuse it for other scenarios, e.g., the Internet of things (IoT) and machine to machine (M2M).

As such, new technologies have been introduced to support voice directly on LTE networks. Voice over LTE (VoLTE)—a voice technology based on the IMS network, and Voice over Wi-Fi (VoWi-Fi)—technology that uses Wi-Fi access to help operators offload their congested LTE networks.

The next and biggest challenge in today’s context of growing bandwidth consumption, and where legacy 2G/3G will continue to coexist with LTE into the foreseeable future, lies in ensuring that multiple voice technologies, such as VoLTE, VoWi-Fi and Voice over circuit switch (VoCS), are able to work flawlessly on their own, in addition to interworking seamlessly with each other. Collectively, these methodologies are known as Voice over X (VoX).

This brings us to the VoX challenge.

Because any degradation or disruption in voice service is perceived immediately, a proactive approach centered on robust, realistic and comprehensive predeployment validation of services is essential to meeting subscriber expectations for high voice quality.

For more information about the benefits and drawbacks of today’s voice technologies, solutions for LTE and 2G/3G legacy networks, and how to manage network resources using VoX, check out our webinar Beyond VoLTE: Voice over X.