Globally, there are over 1 billion 5G connections across the fifth-generation of wireless communication standards, including the 5G standalone (SA) version. While most of these 5G connections are supported by 5G non-standalone (NSA) networks that rely on 4G LTE networks to operate, wireless carriers are increasingly deploying 5G standalone (SA) technology, which is considered “true” 5G. Ultimately, 5G SA will drive new use cases and unlock the advanced capabilities of 5G.
5G standalone (SA) is an implementation of 5G that solely uses a 5G core network, meaning it has no dependency on 4G LTE network control functions, for signaling and data transfer. At-scale, 5G SA will deliver lower costs for wireless carriers, a better user experience, and support new use cases.
Dgtl Infra provides an in-depth overview of 5G standalone (SA), including what it is, its architecture, and its key differences from 5G non-standalone (NSA). Additionally, we detail the deployments and commercial launches of 5G SA made by U.S. wireless carriers T-Mobile, Verizon, AT&T, and DISH Network. Finally, Dgtl Infra explains the key benefits and use cases for 5G SA.
What is 5G Standalone (SA)?
5G standalone (SA) is a new mobile network architecture that is not dependent on existing 4G infrastructure to facilitate communications. Instead, 5G SA networks are built with 5G infrastructure across both the radio access network (RAN) and the core network, coupled with cloud-native principles, such as virtualization, containers, container orchestration, and microservices. In turn, 5G SA networks are more flexible, scalable, and efficient in their use of network resources, which leads to a better end user experience for consumers and lower costs for wireless carriers.
What is the Difference Between 5G Standalone (SA) vs Non-Standalone (NSA)?
The major difference between 5G standalone (SA) and non-standalone (NSA) is in the core network. Specifically, 5G NSA involves laying the 5G RAN over an existing 4G LTE network, whereas 5G SA requires a new 5G packet core network.
For reference, the following illustration shows the architecture and different components of the core network and the radio access network (RAN):
Below are further details on both the 5G SA and NSA architectures, in order to better compare and contrast these two implementations of 5G:
5G Standalone (SA) Architecture
5G standalone (SA) is a completely new mobile network architecture. It enables all of the capabilities of 5G, given that it is not dependent on any existing 4G LTE infrastructure.
5G SA involves a new 5G packet core architecture, which means that 5G services can be deployed without pre-existing 4G LTE equipment in the network. In 5G SA architecture, the 5G RAN and its New Radio (NR) interface, consisting of gNodeB (gNB) macro cell base stations, is connected to the 5G packet core network and operates as a “standalone” entity.
In 5G SA, the 5G core network provides the control plane signaling, while the 5G radio access network (RAN) provides the user (or data) plane, meaning the transfer of data traffic between a user’s device and the network. Therefore, this architecture removes any dependency on the 4G LTE core and radio network.
Additionally, the 5G packet core architecture offers many new, natively built-in network functions and capabilities within those functions. For example, these new capabilities include: network slicing, control and user plane separation (CUPS), virtualization, automation, multi-gigabit per second (Gbps) support, and ultra-reliable low-latency communications (URLLC). As a result, the 5G core network is designed to make full use of the added capacity (throughput) and reduced latency that the new 5G radio (NR) can provide.
5G Non-Standalone (NSA) Architecture
5G non-standalone (NSA) is the first version of 5G network architecture, considered to be a “steppingstone” to the “true” 5G network that is 5G standalone (SA). As the name suggests, 5G NSA is not “standalone”, meaning it is designed to be deployed on top of existing 4G LTE network infrastructure.
5G NSA enables the 5G RAN and its New Radio (NR) interface to be deployed and to connect to a 4G LTE network, meaning 4G radio access for control plane signaling and an evolved packet core (EPC) network. Importantly, in this architecture, the 5G radio (NR) cannot connect to the 4G LTE control plane core network on its own. Instead, the 5G radio depends on the 4G LTE eNodeB (eNB) macro cell base station for all control plane signaling. While the 5G radio (NR) is utilized for the user (or data) plane.
Globally, 5G NSA has been primarily used by wireless carriers to quickly and easily deliver 5G services to end users. With 5G NSA, wireless carriers have been able to offer introductory 5G services to their customers, while using this transitionary time to resolve any issues in the 5G RAN and, in parallel, maintain the stability of the rest of their 4G LTE network. For end users, the initial benefits of using 5G NSA have been better coverage and enhanced throughput over 4G LTE services.
In 5G SA, the core network is built using cloud-native principles, which refers to virtualization, containers, container orchestration (Kubernetes), and microservices. Wireless carriers are using one of the following three cloud delivery models for deploying their 5G SA core network:
- Private Cloud: deploy core functions on-premises through their internal private cloud, which is how they have historically deployed core functions
- Public Cloud: deploy the network entirely on the public cloud through a cloud service provider (CSP), such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud
- Hybrid Cloud: utilize a hybrid cloud approach, meaning a combination of an on-premise data center (or edge location) and a public cloud. Here, the functions are an instance of the cloud service provider (CSP), through services like AWS Outposts, Microsoft’s Azure Stack Edge, or Google Cloud’s Anthos
The 5G SA core network is cloud-native and is designed as a service-based architecture (SBA), which is built with new capabilities like the network resource function (NRF). More specifically, NRF acts as a directory for all available network services, such that they can be easily located and accessed by customers.
5G SA enhances and complements edge computing by allowing data processing and applications to run closer to the end user, at the edge of the network. Specifically, edge computing support facilitates the distribution of user (or data) plane functionality to break out traffic dynamically at the edge. This feature reduces latency and increases service reliability, leading to an improved end user experience.
Ultimately, 5G SA will enable new use cases, particularly for the Internet of Things (IoT), such as connected autonomous vehicles, which require ultra-reliable low-latency communications (URLLC) that can only be achieved at the edge.
5G Standalone (SA) Deployments by Wireless Carriers
Globally, 40 wireless carriers have deployed, launched, or soft-launched 5G standalone (SA) in public networks. This progress compares to a total of 245 wireless carriers that have launched or soft-launched commercial 5G networks, implying ~16% of 5G-focused wireless carriers have made the shift to 5G SA.
Geographically, these launches include wireless carriers in the United States, China, Canada, Brazil, Australia, Japan, South Korea, Singapore, Thailand, Philippines, Taiwan, India, United Kingdom, Germany, Austria, Finland, Saudi Arabia, Bahrain, and Kuwait. While wireless carriers from even more countries have trialed 5G SA.
5G SA – Commercially Deployed and Trialed by Market
Focusing on the United States, T-Mobile, Verizon, AT&T, and DISH Network have all made progress deploying 5G SA, albeit to varying degrees.
T-Mobile – 5G Standalone (SA)
T-Mobile has deployed a nationwide 5G standalone (SA) core network on its low-band 600 MHz spectrum (marketed as Extended Range 5G) and mid-band 2.5 GHz spectrum (marketed as Ultra Capacity 5G). With more of its network traffic migrating to 5G SA, T-Mobile’s spectral efficiency will significantly increase.
Additionally, T-Mobile has partnered with Cisco to launch a cloud-native 5G core gateway, where T-Mobile has moved all of its 5G and 4G traffic. By moving its traffic to the cloud-native core gateway, T-Mobile is immediately delivering more than a 10% improvement in both speeds and latency (more responsiveness) for its customers nationwide.
T-Mobile’s 5G core architecture is based on Cisco’s cloud-native control plane, optimized with Kubernetes-orchestrated containers on bare metal, freeing up over 20% of the CPU (Central Processing Unit) cores.
Voice over New Radio (VoNR)
T-Mobile has launched commercial Voice over New Radio (VoNR) service, using Nokia’s radio and core equipment and Samsung’s Galaxy devices (S21 and S22). Geographically, T-Mobile has lit-up these commercial VoNR services in six cities: Cincinnati, Ohio; New Orleans, Louisiana; New York City, New York; Portland, Oregon; Salt Lake City, Utah; and Seattle, Washington. Notably, T-Mobile was the first wireless carrier in the United States to offer commercial VoNR service for 5G SA.
Beyond this initial launch, T-Mobile has been slowly deploying VoNR across the country and plans to cover 100 million people with VoNR in the coming months.
Note: Voice over New Radio (VoNR) is an important 5G standalone (SA) use case, which is explained in further detail in the final section of this article.
Verizon – 5G Standalone (SA)
Verizon has begun moving customer traffic onto its cloud-native, containerized 5G standalone (SA) core network. The service-based architecture (SBA) of the 5G SA core is built on Verizon Cloud Platform (VCP) and consists of software applications, compute resources, networking, and storage. While Verizon’s 5G SA core network already supports VoNR services, the company has not disclosed its plans for launching commercial VoNR service.
AT&T – 5G Standalone (SA)
AT&T has started deploying its 5G standalone (SA) core network. However, the company has not begun moving customer traffic onto its 5G SA core, and does not intend to do so, until the smartphone and tablet market matures. Specifically, AT&T has cited battery life as the primary concern for devices constantly connected to 5G SA. Therefore, only when smartphones and tablets become more power-efficient will AT&T begin moving customer traffic onto its 5G SA core.
AT&T’s cloud-native approach to its 5G SA core network is centered on a partnership with Microsoft Azure. Over the next few years, AT&T will move its 5G mobile network to the Microsoft cloud, with its mobile network traffic being managed using Microsoft Azure technologies.
DISH Network – 5G Standalone (SA)
DISH Network is building the nation’s first cloud-native, Open Radio Access Network (O-RAN) based 5G standalone (SA) network. To-date, DISH has started construction on over 15,000 5G sites, which, when completed, are capable of providing broadband coverage to over 60% of the U.S. population.
DISH’s cloud-native approach to its 5G SA core network involves a close partnership with Amazon Web Services (AWS). Particularly, DISH is utilizing a number of AWS cloud services and infrastructure, including Amazon Elastic Compute Cloud (EC2), Amazon Elastic Kubernetes Service (EKS), AWS Local Zones, and AWS Outposts.
Additionally, DISH has partnered with VMware to use its Telco Cloud platform, which runs on Kubernetes and provides an abstraction layer across multiple network domains. VMware’s Telco Cloud will enable DISH to virtualize their network functions, as well as dynamically move and scale workloads within the public cloud, based on consumer demand.
Voice over New Radio (VoNR)
DISH’s wireless network is capable of offering Voice over New Radio (VoNR) services in over 100 markets, through band n70 (AWS 2-4 spectrum). However, presently, the company delivers commercial VoNR services across only 12 large markets, covering a total of 30 million people, including the cities of Cleveland, Dallas, Houston, and Las Vegas. Furthermore, DISH expects to grow its VoNR coverage by ~50% each quarter, with the goal of offering VoNR to 70% of the U.S. population within the next twelve months.
What are the Benefits of 5G Standalone (SA)?
The key benefits of 5G standalone (SA) are new business opportunities, enhanced end user experience, network efficiency, and less complexity, as compared to 5G non-standalone (NSA).
1) New Business Opportunities
5G standalone (SA) enables new services and use cases, new market segments, and a new 5G core network. Examples of new 5G SA use cases are Voice over New Radio (VoNR), network slicing, and time-critical communication. Further details on these new 5G SA use cases are provided in the next section.
2) Enhanced End User Experience
5G standalone (SA) enables end users to get instant access to 5G, particularly for wide 5G bands, which deliver higher throughput and lower latency. Additionally, 5G SA produces better uplink coverage because there is no power split between user equipment using 4G and 5G.
3) Network Efficiency
5G standalone (SA) extends coverage through carrier aggregation, which allows multiple frequency bands to be combined together. For example, aggregating a 5G low-band frequency with a 5G mid-band frequency can improve mid-band coverage by up to 2.5 times and increase the population that can be supported by the mid-band frequency by up to 25%. Also, in 5G SA, more LTE traffic can be offloaded on to mid-band 5G – which uses spectrum more efficiently than 4G – leading to an overall capacity increase of 27%.
4) Less Complexity
5G standalone (SA) offers network simplicity by using both a 5G radio access network (RAN) and a 5G core network. Additionally, device simplicity results because smartphones and tablets are being built to connect to these end-to-end 5G networks.
Overall, these benefits contribute toward the fundamental improvements of 5G over 4G LTE, which include lower latency, increased speed, higher density (# of connected devices), added capacity (network throughput), and energy efficiency.
READ MORE: What’s the Difference Between 4G LTE and 5G?
Use Cases for 5G Standalone (SA)
Examples of important use cases for 5G standalone (SA) are Voice over New Radio (VoNR), network slicing, and time-critical communication.
Voice over New Radio (VoNR)
Voice over New Radio (VoNR), also known as Voice over 5G (Vo5G), is a method that enables voice calls to be made over 5G SA networks, without relying on LTE as the anchor. VoNR is the successor to Voice over LTE (VoLTE), which allows voice calls to be made over 4G LTE networks.
VoNR provides higher-quality voice calls than VoLTE because 5G networks deliver lower latency and wider bandwidths, which results in:
- Lower Latency: slightly faster call set-up times, meaning less delay between the time a customer dials a number and when the phone starts ringing. Also, there will be less delay between when someone speaks and when the other person hears it
- Wider Bandwidths: higher-quality audio when someone speaks
In VoNR networks, 5G voice calls are implemented as end-to-end VoIP connections managed by an IP Multimedia Subsystem (IMS) core. The IMS is used with specific profiles for control and user (or data) planes of voice service on 5G, resulting in voice service being delivered as data packets over the 5G network.
Ultimately, VoNR and Video over New Radio (ViNR) will allow for new experiences in 5G SA networks, such as immersive videoconferencing, as well as augmented reality (AR) and virtual reality (VR) applications.
The 5G SA core network supports end-to-end network slicing, which enables physical network resources to be virtually partitioned or “sliced” into multiple independent networks using different segments of the same spectrum band. These network slices can then be dedicated to specific use cases or applications.
Network slicing is an important use case of 5G SA because it helps to optimize network capacity and ensure that resources are allocated efficiently. Notably, network slicing optimizes resource allocation using automation, software-defined networking (SDN), and network functions virtualization (NFV).
READ MORE: Software-Defined Networking (SDN) Explained
Time-critical communication, through the use of 5G SA’s ultra-reliable low-latency communications (URLLC) capabilities, can deliver data within a specific time window required by an application.
As shown below, a system designed for enhanced mobile broadband (eMBB) maximizes data rates without any guarantee regarding latency. In contrast, time-critical communication is designed to secure data delivery within specific latency bounds (X ms) with the desired reliability (Y percent).
Use case categories for time-critical communication include:
- Real-Time Media: time-critical communication enables the offloading of processing and rendering to the mobile network edge, thus supporting applications where media is produced and consumed in real-time. Examples of these applications are cloud gaming, cloud-based augmented reality (AR) & virtual reality (VR), and remote learning
- Industrial Automation: time-critical communication supports real-time information exchanges between controllers, sensors, and actuators, which is critical for Industrial Internet of Things (IIoT) applications. Examples of these IIoT applications are process monitoring and control, smart grid control, and machine vision for robotics
- Remote Control: time-critical communication enables real-time sensor information to be exchanged between a teleoperated machine or vehicle and a remote operator. Importantly, remote control can improve working environments by removing humans from inconvenient or hazardous situations
- Mobility Automation: time-critical communication supports real-time information exchanges between moving vehicles and/or robots and the environment, for control and coordination. Examples of these applications include automated guided vehicles (AGVs) and autonomous mobile robots (AMRs)