The fifth generation of mobile networks (5G) has already been introduced in many countries. Now with 5G, 4G, 3G and 2G networks live at the same time, there are quite a few terminologies out there that can cause confusion. One such terminology is VoLTE or Voice over LTE, a 4G technology that also works in the 5G networks. This post aims to outline the difference between these two technologies.
VoLTE (Voice over LTE) is a technology that was developed for 4G LTE however it can be used by both 4G and 5G networks. Enabling VoLTE in a network requires IMS (IP Multimedia Subsystem) and a 4G core network (EPC). Non-standalone 5G (NSA) uses a 4G core network and therefore can benefit from VoLTE.
VoLTE is a technology within 4G
VoLTE stands for Voice over LTE (Long Term Evolution), and it is a capability in 4G LTE networks that allows voice calls and text messages over the IP network. Unlike the legacy 2G and 3G networks, 4G LTE networks do not have a circuit-switched function. Therefore, all services are delivered through the packet-switched network where the 4G core network (Evolved Packet Core – EPC) works alongside IMS (IP Multimedia Subsystem) to deliver communication services in the form of data packets. Since voice is an essential service for an operator, VoLTE is fully managed by the operator and follows specifications to ensure an end-to-end quality of service (QoS). For VoLTE to work, it must be supported by the network and the device. For scenarios where the network or device do not support VoLTE, there is a 2G/3G fallback option called Circuit-Switched Fallback (CSFB). The VoTLE capability can work in both 4G and 5G networks. You may check out our detailed post on VoLTE to learn how to locate it on your phone.
5G is a cellular technology
5G is the fifth generation of mobile networks enabled by the technology New Radio or NR. 5G networks are expected to coexist with the 4G LTE networks for a long time to jointly cater to a wide range of use cases such as high-speed broadband, IoT (Internet of things) device support, self-driving cars, smart cities and many more. While supporting all these advanced services, 5G will still facilitate one of the most basic services, voice calling. Voice calling has been an essential part of mobile networks ever since they were introduced in the early 1980s. Since then, the technologies behind voice calling have evolved considerably, but the value of carrier-grade high-quality voice service has not changed. Like 4G LTE, 5G NR networks also operate using the packet-switched capability. Since 5G NR networks do not have the circuit-switched part, the voice calls and SMS are IP-based and facilitated by the same packet-switched network that enables mobile data. However, in 5G networks, the voice calls can be enabled by either VoLTE or a 5G version of VoLTE called Voice over NR or VoNR. 5G networks have two deployment modes: standalone or non-standalone. In the standalone deployment model, 5G networks have their own radio and core networks. The non-standalone 5G, on the other hand, only has a 5G radio network which works with an upgraded version of the 4G core network (EPC). In non-standalone deployment, the 4G core network (EPC) works with IP Multimedia Subsystem (IMS) to enable voice calls in 5G networks through the VoLTE technology. However, in the standalone 5G deployment, the 5G core network directly works alongside IMS to facilitate voice calls through Voice over New Radio or Voice over NR (VoNR).
VoLTE stands for Voice over LTE and is a 4G technology that enables voice calls and text messages in 4G LTE and 5G NR networks using the packet-switched capability. 5G stands for the fifth generation of mobile networks and is the latest cellular technology in mobile communications that supports VoLTE as well as Voice over NR (VoNR) for voice calls and text messages.
Here are some helpful downloads
Thank you for reading this post, I hope it helped you in developing a better understanding of cellular networks. Sometimes, we need some extra support, especially when preparing for a new job, studying a new topic, or maybe just buying a new phone. Whatever you are trying to do, here are some downloads that can help you:
Students & fresh graduates: If you are just starting, the complexity of the cellular industry can be a bit overwhelming. But don’t worry, I have created this FREE ebook so you can familiarise yourself with the basics like 3G, 4G etc. As a next step, check out the latest edition of the same ebook with more details on 4G & 5G networks with diagrams. You can then read Mobile Networks Made Easy, which explains the network nodes, e.g., BTS, MSC, GGSN etc.
Professionals: If you are an experienced professional but new to mobile communications, it may seem hard to compete with someone who has a decade of experience in the cellular industry. But not everyone who works in this industry is always up to date on the bigger picture and the challenges considering how quickly the industry evolves. The bigger picture comes from experience, which is why I’ve carefully put together a few slides to get you started in no time. So if you work in sales, marketing, product, project or any other area of business where you need a high-level view, Introduction to Mobile Communications can give you a quick start. Also, here are some templates to help you prepare your own slides on the product overview and product roadmap.