5G

Seven years after its commercial launch, 5G covers more than half the world’s population – making it the fastest-adopted mobile technology in history. And yet, the question keeps coming up: is 5G actually delivering on its promise?

The honest answer is: it depends on who you ask. For consumers, 5G has largely meant faster and better quality video streaming. For network engineers and communication service providers (CSPs), the picture is more complex – and more interesting. There are real gains in capacity, energy efficiency and IoT connectivity. There are also genuine challenges in monetisation, network optimisation and the technical complexity of 5G Standalone (SA) deployments.

Let’s look at 5G from multiple angles – the technology evolution, the benefits, the obstacles, and where the industry stands today. If you work in telecoms or enterprise networking, this is the context that matters.

Over-the-top (OTT) applications rely on sufficient network bandwidth. 4G networks can provide enough bandwidth, and the latency, jitter and packet loss are often acceptable, however the limited bandwidth of the 4G network may cause undesirable user experience. 

5G is the fifth generation of wireless cellular communications and mobile network technology succeeding 4G. It uses 5G New Radio (5G NR) that offers 10-100x faster speed with a much lower latency.  

The following diagrams illustrate technology of the 4G and 5G core.

Simplified 4G EPC Architecture and 5G NSA

5G can use the same packet core as 4G. This setup is called 5G Non-standalone (NSA). 5G NSA offers a simpler migration from 4G to 5G due to the same core as with 4G.

5G standalone (5G SA) uses a new 5G cloud native core for control plane. User Plane traffic is handled by User Function (UPF). When 4G relies on MME, 5G uses AMF, SMF and AUSF. 5G handles SGW/PGW functions with SMF and UPF. 5G SA has lower latency and it is capable of offering services previously not possible.

Simplified 5G SA architecture

Global System for Mobile Communications Association (GSMA) notes that seven years after the commercial launch of 5G in 2019, the global connectivity landscape has reached a new phase in its evolution. At the end of 2025, more than half of the world’s population was covered by a 5G network, making it the fastest‑adopted mobile technology to date. 

GSMA uses the 5G Connectivity Index (5GI) based on 5G Infrastructure, services, coverage, performance, adoption, usage, affordability and the regulatory environment. The leaders measured by 5GI are the Gulf Cooperation Council (GCC) states, Nordic countries, developed Asia Pacific, Mainland China and the US.

Despite the fast adoption there are challenges. From the Communication Service Provider (CSP) perspective the biggest challenge is the monetization, which was already a challenge with 4G – not only a 5G problem. Some markets, China, GCC and the US see accelerated enterprise digital transformation, speed-based mobile broadband pricing and the use of 5G FWA. CSPs are actively expanding the use of AI to enable automatic operations. This process is easier if 5G SA and 5G Advanced are deployed.

It is typical for a cellular network to have varying quality in different areas, for example, related to the coverage and/or capacity. User traffic may be focused on hot spots and therefore, a careful and continuous network optimization is needed. Without good network optimization it is possible that 5G does not exceed 4G performance. This is an area where all CSPs are automating the network optimization using also AI.

For some, 5G may be a disappointment due to the fact that it was marketed as a revolutionary technology, although in reality, it has been seen only offering speed improvement compared to 4G. Indeed, 5G was advertised to enable virtual reality, remote surgery and autonomous vehicles while consumers wanted to pay less and get more – in practical terms, this meant faster connections and smooth video streaming. 

Technically, it has been challenging for the industry to manage 5G SA. 3GPP 5G standard includes Network Data Analytics Function (NWDAF) as a component to collect data, to analyse and expose data to other network functions. NWDAF however, is not well suited for subscriber-specific data analytics. For this reason, all the network vendors have created their own methods for extracting 5G Core data to analytics tools. In addition to the complexity of data extraction, another aspect is the format of the data extracted. Instead of having interface data as before, 5G SA data extraction is message-based. In multi-vendor core networks, this is especially challenging.

5G is the fifth-generation mobile network technology that brings higher speeds, lower latency, and greater capacity than previous generations. It has the potential to revolutionize various industries, from telecommunications to IoT, enabling advanced use cases like smart cities, autonomous vehicles, and industrial automation.

A 5G system (5GS) includes User Equipment (UE), a 5G Base Station (gNB), and a 5G Core Network (5GC). Together, these components support a wide range of services that 5G networks offer, including:

A 5G System (5GS) consists of User Equipment (UE), 5G Base station (gNB), 5G and a 5G Core Network (5GC) as illustrated in following Figure 1. In 5GS architecture, the 5GC is located at heart and enables the 5G RAN to support 3GPP defined three use cases, i.e. Enhanced Mobile Broadband (eMBB), Ultra-Reliable Low Latency Communication (URLCC) and Massive Machine Type Communication (mMTC).

3GPP has defined 5G Core to utilize cloud virtualisation, service-based architecture (SBA) across all 5G functions and procedures, including authentication, security, session management and aggregation of traffic from end devices. The 5G core network supports the Virtualization of software functions to use NFVI in design 5G Networks, including MEC infrastructure. The new architecture has adopted separation of user plane and control plane functions, which enables independent scaling of the control and user plane functions, e.g. a Mobile Network Operator (MNO) can add more user plane functions without adding more control plane and vice versa depending on deployment strategies. User plane functions could be distributed geographically close to 5G RAN to minimise user plane latency, while control plane functions could be centralised to get benefits of Virtualization.

In ‘Service based’ architecture, the set of Network Elements (NEs) is replaced with a set of Network Functions (NFs). Each Network Function can provide services to other Network Functions, i.e. each Network Function is a service provider. The point-to-point interfaces are replaced by a common bus which inter-connects all Network Functions. The services are specified for the Network Function providing them, instead of each pair providing and consuming Network.

The Network Repository Function (NRF) is the main network function in service based architecture and plays a key role. All network functions register the services they offer with the NRF using the service registration procedure, and later they use the NRF as a database to discover the services offered by other Network with service discovery and service authorization procedure.

Within Service Based Architecture, Network Functions communicate to each other using http protocols defined methods like POST, GET, PUT, PATCH and DELETE.

The Service Based architecture represents a move towards a cloud implementation of the Core Network. Legacy Core Networks have been deployed using separate hardware for each Network Element. Today 5G Core Networks use cloud-native network functions (CNF). Microservices and CNFs provide better resource efficiency, resiliency and higher availability. CNF also promises less downtime in the network.  

5G has several enhancements in subscriber security:

UE keys are stored in the Universal Subscriber Identity Module (USIM) and the home environment to enable network access security. There are two trust domains, tamper proof universal integrated circuit card on which the USIM resides as a trust anchor and the Mobile Equipment.

Subscription Permanent Identifier (SUPI), equivalent to IMSI in 4G, is encrypted and available as SUCI, Subscriber Concealed Identifier. Naturally, the air interface between UE and gNB is encrypted.

CSPs are definitely facing a huge challenge with all the security technologies and threats. It is one thing to secure the network properly, but at the same time, the CSP’s existence and success depends on how well subscribers are served. Understanding subscriber behaviour is even more important than before.

This creates a bit of a dilemma for the CSPs. How to run a secure network and still have visibility in the subscribers?

Network visibility stays as a cornerstone to understanding what happens in the network. Despite the multi-layer security measures, the data flow and messages need to be decrypted before any actions can be done. The point of decryption allows having legitimate extraction of data, for example, from 5GC or User Plane data after it has run through Security GW.

The increasing number of attacks, regulators’ tightened requirements and a massive increase in data volumes demand the CSPs to plan the data extraction points more carefully and, in many cases, even add encapsulated encryption with anonymisation. With careful planning and the right solution, monitoring the data and getting insights into subscribers’ behaviour is still possible.

5G SA represents the next generation of mobile networks that promises to unlock the full potential of enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive IoT use cases. Unlike 5G NSA, which uses a hybrid of 4G and 5G, 5G SA introduces an entirely new core architecture defined by 3GPP. This architecture is based on Service-Based Architecture (SBA) and adopts a cloud-native software approach, enabling dynamic, scalable, and flexible deployments.

The key advantage of 5G SA is its ability to offer greater network efficiency and improved user experiences by harnessing these features. However, this evolution brings unique challenges, especially in terms of network visibility.

In 5G NSA, CSPs could physically tap a link to extract packets for analysis. However, 5G SA complicates data extraction, as Core Network Functions (CNFs) communicate using encrypted HTTP2 messages. Additionally, 3GPP has not standardized a method for mirroring CNF messages in the same way it did for 4G networks.

The Network Data Analytics Function (NWDAF) was introduced to address this challenge. NWDAF is designed to streamline core network data analytics, generating actionable insights and enhancing the end-user experience. However, its implementation is optional, and not every CSP will deploy it in their 5G SA network.

NWDAF faces several challenges:

• Data availability and granularity for subscriber monitoring may be insufficient.
• It may impact network performance, as CNFs must continuously report to NWDAF.
• Integration complexities and alignment with 3GPP standards pose additional obstacles.

Despite these challenges, NWDAF could offer solutions for network analytics, but its effectiveness in providing subscriber behaviour data remains uncertain.

A more cloud-native solution involves using mirrored messages in decrypted form from CNFs, sometimes employing eBPF technology to capture data before encryption. However, these methods also raise concerns regarding data security outside the 5G SBA.

The shift to 5G SA represents a significant technological leap, bringing enhanced security features and a cloud-native architecture. However, monitoring subscriber behaviour and ensuring optimal service performance remain critical challenges. While NWDAF and proxy-based solutions offer some answers, the lack of standardized solutions for extracting decrypted messages hinders widespread adoption.

As 5G SA gains more traction, the demand for more streamlined, standardized approaches to data extraction will grow. CSPs and vendors hope for a solution that offers the necessary granularity for monitoring subscriber behaviour without compromising security compliance with GDPR and other regulations.

For now, CSPs must navigate a complex landscape of multi-vendor CNFs, diverse data extraction methods, and the challenges of encrypted communication in a 5G SA environment.