VoLTE (Voice over LTE)

VoLTE (Voice over LTE)

Realising revenue potential with Voice over LTE  

What is VoLTE?

VoLTE stands for ‘Voice over Long Term Evolution‘. Utilising IMS technology, it is a digital packet voice service delivered over IP via an LTE access network.

Voice calls over LTE are recognised as the industry-agreed progression of voice services across mobile networks, deploying LTE radio access technology.

Who is VoLTE valuable for?

  • Operators
  • OEMs
  • Network vendors
  • Partners
  • Consumers

What are the benefits of VoLTE?

The implementation of VoLTE offers many benefits, both in terms of cost and operation. VoLTE:

  • Provides more efficient use of spectrum than traditional Voice
  • Meets the rising demand for ‘Richer’, more reliable services
  • Eliminates the need to have Voice on one network and data on another
  • Unlocks new revenue potential, utilising IMS as the common service platform
  • Can be deployed in parallel with video calls over LTE and RCS multimedia services, including video share, multimedia messaging, chat and file transfer
  • Increases handset battery life by 40 per cent (compared with VoIP)
  • Delivers an unusually crisp calling experience
  • Provides rapid call establishment time

What is the GSMA doing to help with VoLTE deployment?

Our goal is to achieve a consistent, industry-wide approach to delivering services for LTE. They will embody the following principles:

  1. Promote scale. For VoLTE/video calls over LTE implementation to work, this needs to be based on a single technology and not undermined by fragmentation or diversity. It must work throughout a community of 6 billion+ connections (and growing) and across all networks and devices.
  2. Reduce complexity. A common implementation, adhered to by all, would allow messages and media to be delivered in the best way. Providing consumers with the best quality experience. However, lack of common deployments between networks can detract from the overall quality of the voice/messaging service (e.g. end-to-end HD voice).
  3. Enable Interconnect and Roaming. Seamless roaming can be optimised in the all-IP world. That is if all parties adhere to a single, common implementation of interfaces between every device and network.
    These three principles will underpin how Voice, SMS and RCS will work in the future. They will define the interfaces for end-to-end calling structures, which facilitate interconnect and roaming.

Discover more about Voice over LTE

For more information regarding VoLTE, explore our invaluable resources, Technical support.

“With the support of the GSMA and the Ministry of Science, ICT and future planning, The Republic of Korea were recognised as not only the first country to have launched interconnected VoLTE but also the first country to have migrated its subscriber base to be fully VoLTE interconnected between three operators.”

Sang Heon Lee, SVP, SK Telecom/Sung II Jang, General Manager/Team Leader, SK Telecom
Sung Won Yan, General Manager, KT
Kyung Joong Park, General Manager/Team Leader, LG Uplus

Additional Resources

VoLTE Publications

Deploying Enriched Communications – the cost of indecision and inaction for operators


Wednesday 22 Jul 2015 | HD Voice | Qos IP Interconnect | Resources | VoLTE |

Operators who still have not committed to launch Enriched Communications using IP-based services may not be aware of the scale of the impact of this indecision on their business. This slide pack highlights nine key issues that could ...

A burning platform – the need for action


Wednesday 22 Jul 2015 | HD Voice | Qos IP Interconnect | RCS | Resources | VoLTE |

The crowded nature of IP Communication Services market with low barriers to entry for alternative communication suppliers is creating a problem for operators. This slide pack gives some qualitative and quantitative data as an overview ...

Building the case for an IP-communications future – GSMAi Report – Download Now!


Thursday 26 Feb 2015 | IP Communications | Resources | VoLTE |

GSMA Intelligence is today publishing a report on the case for operator-provided IP-communications, and the future of Voice over LTE, Video over LTE, and Rich Communication Services (RCS). Mobile communication has evolved ...

FCM.01 – VoLTE Service Description and Implementation Guide (Version 2.0)


Friday 17 Oct 2014 | Resources | VoLTE |

Voice over Long Term Evolution (VoLTE) is the industry recognised solution for providing a rich multimedia HD Voice service over the LTE access technology. VoLTE utilises IMS technology and provides a common platform in which to ...

China Unicom – Openness and Cooperation: Achieving a win-win for Telco and OTT


Monday 28 Jul 2014 | RCS | Resources | VoLTE |

Despite suffering significant losses in their core voice and messaging revenues in recent years, operators now recognise OTT service providers are here to stay. Agile OTT players have progressed quickly by delivering in-demand services ...

Ericsson Mobility Report


Thursday 5 Jun 2014 | Resources | VoLTE |

On the pulse of the Networked Society - Ericsson has performed in-depth data traffic measurements since the early days of mobile broadband from a large base of live networks covering all regions of the world.   The aim of this report ...

VoLTE or VoIP over LTE – Who is the ultimate winner?


Thursday 27 Mar 2014 | Resources | VoLTE |

There are multiple options available today for mobile applications. This includes Over-The-Top (OTT) applications, services that are generally offered by third party (non-operator) developers that can be downloaded from popular app ...

Validating VoLTE: A definitive guide to successful deployments


Sunday 25 Aug 2013 | Resources | VoLTE |

This book outlines a VoLTE (Voice over Long Term Evolution) test plan that ensures a correct, stable, and effective VoLTE deployment. These scenarios cover major functional and characterization requirements of a VoLTE network. Each ...

FCM.01 – VoLTE Service Description and Implementation Guide (Version 1.1)


Thursday 5 Dec 2013 | Resources | VoLTE |

Find out about what a VoLTE deployment entails (for single network interconnect and roaming deployments) and gain insight from existing trials, commercial deployments and live operations. The guide builds on existing GSMA Product ...

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VoLTE News

GSMA VoLTE Interoperability Test Event (VITE)

The GSMA is organising a VoLTE Interoperability Test Event, called VITE for short, with the goal of accelerating the implementation of stable interoperable VoLTE devices and networks. It will achieve this through the execution and analysis of an agreed set of test cases in ...

Building the case for IP-Communications

Mobile communication has evolved dramatically over the past twenty years, from the advent of SMS and mobile messaging, to the emergence of smartphones and the mobile application ecosystem. Innovative third-party providers running ‘over the top’ of mobile operator’s high ...

GSMA VoLTE Roaming initiative supported by leading operators from China, Japan and Korea.

The GSMA has organised a collaborative initiative supported by leading mobile operators in China, Japan and Korea including China Mobile, KT, NTT DOCOMO, SK Telecom, KPN and Verizon, to assess various important aspects of VoLTE Roaming with S8 HR and LBO VR (Local Break Out, ...

Network 2020 VoLTE eco-system test event

The GSMA is progressing with its plans for a VoLTE eco-system test event to occur in the first half of 2015. The objective is to set up and execute this test event using principles and lessons learned from the highly successful RCS Meta events which were held in 2012-2013. ...

AT&T and Verizon Wireless get themselves connected

Interconnecting networks between mobile operators offers many benefits to customers such as interoperable VoLTE (voice over LTE) calls with HD Voice quality as well as interoperable Rich Communications Services (RCS). It works by using all-IP (Internet Protocol) technology, ...

All-IP Mobile Communications

The ‘Green Button Promise’ is a key focus area within the Network 2020 Programme. With support from a number of our eco-system partners, we have created an exciting video to demonstrate All-IP Communications in action on a commercial LTE network. This is the first time this ...

VoLTE Service Description and Implementation Guide (Version 2.0)

Voice over Long Term Evolution (VoLTE) is the industry recognised solution for providing a rich multimedia HD Voice service over the LTE access technology. VoLTE utilises IMS technology and provides a common platform in which to provide an enriched calling experience by ...

LTE in the new iPhone and growing around the world

Apple supports LTE in its iPhone 6 – The recent launch of the Apple iPhone 6 and iPhone 6 Plus has created a massive wave of interest with a staggering rush to pre-purchase. For operators, there is a significant feature included – LTE. The device is LTE-ready for some ...

Long Term Revolution: VoLTE Comes of Age

We first discussed the speed of operator Voice over Long Term Evolution (VoLTE) deployments back in June when there seemed to be a never-ending parade of news outlining operator commitments and plans. Three months on and we are starting to see some real traction in the ...

Mobile 360 Series, North America – LTE and Interoperability highlighted

The GSMA held its North American event on the 22nd and 23rd September in Atlanta. A two day Conference Agenda was supported by a small demonstration area showcasing the GSMA’s main Programmes – and Network 2020 was, of course, promoting IP Communications. Unsurprising, with ...

GSMA expands its support for IP Communication Launches and Interoperability Testing

Helping operators and OEMs to reduce the time to market and speed up the launch process for IP Communications is a vital part of the Network 2020 Programme’s work. The GSMA has two teams dedicated to this task, and has recently expanded their scope and activities to provide ...

Loud and clear: operators moving the future of voice on

It won’t have escaped your attention that over the past few weeks a number of global operators have made significant announcements regarding Voice over LTE (VoLTE) deployments, particularly in Asia and North America. Operators including AT&T, NTT DOCOMO, PCCW-HKT, ...