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Voice over 5G (Vo5G) core

Build IMS voice communications into your new 5G services

Voice communications are essential to service providers’ bundled offers. Mobile subscribers expect it as a given component of their plans, and it plays a role in many of the new data services enabled by 5G.

Successful launches of new 5G technology must include a plan for embedding voice into 5G services. Voice communications are provided by an IMS core for Voice over LTE (VoLTE) and Voice over New Radio (VoNR). Introduction of VoNR is made smoother if the operator has already deployed LTE and VoLTE extensively.

5G Voice: There are two ways for operators to leverage voice in 5G.

  • VoLTE: When no 5G Core is deployed, the operator can rely on the underlying VoLTE network including LTE Radio, EPC and IMS to deliver Voice for 5G users while 5G eMBB services are delivered through 5G Radio and the enhanced LTE/EPC.
  • Vo5G/VoNR: When 5G Core is deployed, voice is leveraged using the 5G Core functions and IMS, while the 5G use cases are delivered by the NR and the 5G Core.
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Vision for the future of voice

5G will complete the voice core evolution to IMS, which in mobile networks, began with LTE. Open collaboration with many developers in the extended voice ecosystem will be key to this expansion to new industry verticals.


The vision for the future of voice services

Re-invent voice with Nokia IMS

With 4G, IMS voice enables crystal clear calls. But with 5G, new immersive voice and video experiences are possible, for consumers and businesses.

Revitalize voice! With Nokia IMS, you can make voice a highly valued, must have service that wins new revenue for multiple customer segments.


Re-invent voice with Nokia IMS

Converged Voice Services

Converged Voice Services

Smooth evolution to voice over 5G with IMS core

The future of voice services as heading to Voice over NR (VoNR)

In a 5G world, voice services will depend on the presence of an IMS core network regardless of the deployment path. 5G will enable a wide range of truly novel applications where voice will play an important role. Voice is also a key component of 5G service bundles that form attractive, full featured offers to customers.

White paper
Voice over 5G: the future of voice services

Voice over 5G: the future of voice services

Deployment scenarios supporting Voice over 5G

There are several options for deploying 5G and the way voice service is provided will depend on which option is chosen.  

Nonstandalone (NSA) Option 3x is used in early 5G deployments. Voice services are provided in this approach by the existing 4G VoLTE network. The 5G connection is used for data only.  

Standalone (SA) Option 2 requires deploying the 5G Core. Voice services remain in 5G, along with data services.  

In every deployment option, the 3GPP IP Multimedia Subsystem (IMS) is used as the technology basis to provide voice and video communication services over respectively LTE for option 3x and 5G for option 2. Planning for 5G introduction always includes a discussion around IMS and preparation of the existing 2G, 3G, or 4G network. Initial deployments begin with EPS Fallback, followed by the introduction of VoNR. 

White paper
Paper: Deployment scenario

Deployment scenario

Implementing EPS fallback or VoNR in Standalone 5G core

Implementing EPS fallback or VoNR in Standalone 5G core

Readying your VoLTE network for successful 5G voice implementation

5G must be fully integrated with existing legacy technologies. Tight 5G/LTE integration is essential to maintain high-quality voice services and to ensure seamless call continuity when users move between different access technologies. Voice over 5G (Vo5G) and VoLTE are just different ways to access the same IMS-based voice services. This means that any investments you make in today’s IMS-based VoLTE will support future Vo5G services.

White paper
Paper: Readying your VoLTE network

Readying your VoLTE network

Why VoLTE is a critical enabler for 5G voice services

Deploying VoLTE is strategically important and is typically part of the migration of voice services from 3G and legacy CS mobile networks to the 4G LTE network. VoLTE is based on the IMS architecture, so the rise of VoLTE also coincides with Communication Service Provider (CSP) adoption of IMS.

White paper
Paper: Why VoLTE is a critical enabler

Why VoLTE is a critical enabler

The enterprise opportunity for Communications Service Providers to provide 5G voice services

5G combines Service Based Architecture (SBA) and cloud-native software with open interfaces and network slicing. These key concepts come together to deliver the flexibility, granularity and scalability that allow CSPs to create highly customized virtual networks for individual enterprise needs. Voice will remain an important part of enterprise ommunications, complementing additional services that will emerge.

White paper
Paper: The enterprise opportunity for Communications Service Providers

The enterprise opportunity for Communications Service Providers

The 5G ecosystem for voice networks to build and embed voice services to 5G use cases

Voice may be integrated as a component of new 5G services or become part of a bundled CSP package. 5G core openness and programmability through open Application Programming Interfaces (APIs) exposed by our Network Exposure Function (NEF) enables creating services for new vertical segments and enriching their consumer and enterprise offers. A wide range of API sets may be involved for service creation to enable the voice network evolution. Our Telephony Application Server (TAS) provides multiple IMS application server roles to deliver high quality voice, video and messaging services for all mobile and fixed networks.

White paper
Voice over 5G: The ecosystem for voice networks

Voice over 5G: The ecosystem for voice networks

Invent new 5G voice services

Exploit infinite possibilities provided by telco APIs and integrate it to services of other domains. Nokia voice core ensures agile service creation, reduces complexity and increases time-to-market. Be customer-centric with new Open business models.


Vanishing boundaries between IT and telco with Open APIs in 5G voice services

We are evolving mobile voice services to converged voice with 5G core including Voice over Wifi (VoWifi)

The access agnostic 5G core supports fixed and wireless connectivity that includes licensed, unlicensed, 3GPP and non-3GPP technologies, to deliver converged voice services. Nokia IMS-based product portfolio gives field-proven, efficient and robust voice and multimedia services with any access type including Voice over Wifi (VoWifi) using one voice core.

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