In competition with messaging services and Facebook and Instagram timelines, is voice telephony at all relevant in 2017 and beyond? We believe: yes, absolutely! Telephony is still the most direct and most efficient way of telecommunication. Apart from being an auditory interaction, voice still transports much more emotion – and opportunity for clarification – than any emoticon ever could. Or, as I recently read on a funny postcard: “Why five minutes of calling when I can do the same in two hours of texting?”

For decades, telephony was associated with public fixed-line telephony. The emergence of cellular or mobile telephony produced the installation of parallel networks with gateways to the common telephony system. A cell phone brought the huge advantage of mobility, and making a phone call was possible from more or less anywhere. For this, mobile subscribers put up with lower voice quality and lower reliability for a long time.

What does voice telephony stand for in 2017?

Today, in areas with good coverage, a mobile network reaches levels of reliability that are close to those of a fixed-line service. In voice transmission, cellular networks are even superior to fixed-line services because they support a wider audio band in HD-voice. Surprisingly, however, this excellence in voice quality is lost when passing through a gateway into a fixed-line network.

To remedy this problem, operators have begun to fully integrate their mobile and fixed networks on the basis of packet-based transmission, as in LTE and IP, and IP-based signaling. This convergence enables subscribers to appreciate their mobile phone’s audio quality and selected services also in their fixed-line subscriptions. Consequently, telephony in 2017 is becoming an integrated network offering many services and best voice quality at any place and any time – regardless of whether at home or on the go.

What are the latest technical improvements in (mobile) telephony?

So, yes, we believe in voice telephony. And apparently so do network operators. When perusing tech magazines that benchmark and rate mobile network operators, a significant 40% of the rated network performance is allocated to telephony, while data and video services make up for the rest.

It is no wonder that network operators continue to invest in improving voice telephony. Not only is this a load-driven move towards voice over LTE (VoLTE) but also an investment in better voice quality. First, operators moved away from traditional narrowband telephony (the typical telephone voice we’ve known for decades) towards HD-voice, transmitting in a wider audio spectrum up to 7000 Hz. By doing so, voice quality was improved, but did not free up any network capacity. Nevertheless, the investments paid off.

Competing voice telephony services

The emergence of new and competing voice services further underscores the importance of telephony. Remember Skype being the first to offer free telephony over the Internet? Today, every popular messenger service supports telephony, even video telephony. These services generally offer good voice quality and wide audio, in some cases even wider than that of pure mobile HD-voice services. They are easy-to-use, quite reliable even in mobile environments, and free of charge – apart from potentially incurring costs for the data connection. Fully benefitting from telecom operators’ network infrastructure, they can even handle handovers from Wi-Fi to cellular technologies.

voice telephony

Third-party voice services, including Skype, Facebook, and Whatsapp calling, are challenging traditional voice telephony services.

Network operators thus are not only challenged by their direct competitors but also by third-party telephony services using their infrastructure. While mobile network operators can still count on higher reliability and more privacy, third-party telephony services are slowly closing that gap, too. And with audio quality no longer being a differentiator …

… the race for yet better voice quality is on. The initial step is taken again by operators: they have been rolling out support for the new full-HD voice quality codec EVS (Enhanced Voice Services) that extends the audio spectrum towards 16,000 Hz in telecommunications.

EVS underlines the importance of voice telephony

Technically, use of this spectrum translates into FM radio quality, and it even leaves room for further improvement. While previous codecs have been strongly optimized for human voices, the new EVS also significantly improves music and other types of audio. This also helps to understand the person at the other end of the line in noisy environments, facilitating multiparty tele-conferencing because individual voices are easier to discern.

EVS coded speech is transmitted via the same channel capacity as previous voice codecs; and, as with HD-voice, EVS does not free up any network capacity. The sole purpose of this huge investment is to improve voice quality and user perception and therewith overall customer satisfaction with voice telephony services. EVS underlines the importance of voice telephony in operating networks and doing business in 2017 and beyond.

In my next post about enhanced voice telephony, read how we measure the new voice codec EVS, how the end user perceives it, and how it works.

Until then, take the call, stay connected, and get a glimpse into the first real live network EVS measurements conducted together with our partner NET CHECK.