5G Non-Standalone is vulnerable to denial of service. Transitioning to 5G will involve multiple stages, according to the 3GPP roadmap. One of these stages, 5G Non-Standalone, combines use of 5G New Radio and an LTE network core. As a result, these networks inherit all the vulnerabilities of LTE networks from the get-go. Research indicates that 100 percent of LTE networks are vulnerable to denial of service (DoS) through Diameter exploitation. This means that 100 percent of 5G Non-Standalone networks will be vulnerable to DoS, too.
Hacking 5G could become as simple as hacking the web. The 5G network core will be based on software-defined networking (SDN) and network function virtualization (NFV). SDN and NFV make heavy use of the HTTP and REST API protocols. These protocols are well known and widely used on the Internet. Tools for finding and exploiting vulnerabilities are available to any adversary. And now, these protocols will also be used on 5G networks. Consider the current situation with web security: despite the best efforts of the IT and security industries, well-protected websites are the exception rather than the rule. Software development is rife with mistakes that impact security. The average web application contains 33 vulnerabilities and 67 percent of web applications contain high-risk vulnerabilities. Lowering the barrier to entry will pave the way for an upswing in attacks on 5G networks.
More flexibility. More configurations. More errors. When performing security analysis of mobile operator networks and corporate information systems, our experts routinely find dangerous configuration flaws. Even with today's 4G networks, not every operator succeeds in securely configuring the core network and protecting it from all angles. As SDN and NFV are implemented for network slicing in 5G, administration will become even more difficult. Flexibility in 5G networks comes at the cost of increased complexity and settings to monitor. This flexibility means a higher likelihood of security-busting configuration mistakes.
Millions of connected IoT devices offer a bonanza for botnets. Most user equipment on 5G networks will not be consumer phones or computers, but IoT devices. By 2020, there will be about 20 billion such devices. The number of attacks on the IoT is increasing. Device protection is poor and malware distribution is easily scalable. In the last year alone, our experts found 800,000 vulnerable devices. Mirai was an example of the destructive capacity of a large botnet. To avoid a new Mirai and the threat of disruption of user service, 5G network operators will have to develop new threat models more attuned to these realities.
Each new generation of mobile standards since 2G has been designed for one and the same goal: to boost bandwidth on packet networks. Faster Internet access is the name of the game. Other changes have been minimal. The voice codec in 3G changed only slightly. On 4G networks, voice traffic is transmitted over packet data using the IP Multimedia Subsystem (IMS), which many operators have not deployed. The 4G network may not transmit voice at all, instead falling back on 2G/3G to make calls. Yet recent mobile networks have certain drawbacks compared to their predecessors. 3G and 4G in particular are a less-thanideal fit for the IoT: compatible devices need to have high performance and corresponding high energy consumption. As a result, devices require frequent charging or battery swaps. This is unacceptable for many IoT devices, which may require battery life of up to 10 years without swapping or charging batteries.
5G networks are designed to account for such diverse needs. They can provide superfast access with minimal latency. At the same time, they retain the flexibility to provision slower speeds with lower device resource requirements.
According to 3GPP Release 15 for 5G, which came out in summer 2018, the first wave of 5G networks and devices is classified as Non-Standalone (NSA). 5G radios will be supported by existing 4G infrastructure. In other words, devices will connect to 5G frequencies for data transmission when needing greater bandwidth and lower latency (such as for communication between smart cars), or to reduce power draw on IoT-enabled devices, but will still rely on 4G and even 2G/3G networks for voice calls and SMS messaging. So, at least during the transition period, future 5G networks will inherit all the vulnerabilities of previous generations.
5G Standalone networks may add new types of security flaws, because the entire packet core and additional services will depend on virtualization. Technologies such as NFV and SDN will make deployment simpler, faster, and more flexible. But replacing dedicated hardware with software-defined systems (some of them based on open-source code) may prove a double-edged sword that makes mobile networks more vulnerable to attacks.
One thing is for certain: availability, integrity, and confidentiality will remain the foremost concerns. As 5G begins to penetrate every area of life—such as manufacturing, healthcare, and transport—emboldened malefactors will surely follow with close interest.
The transition to 5G will be gradual. Standards have not been fully finalized yet and 5G networks are expected to initially rely on and integrate with previous-generation networks, slowly displacing them over time.
Standards-making for 5G networks, including development of plans for future specifications, kicked off at the September 2015 workshop held by 3GPP. As planned, Phase 1 specifications were to describe the architecture for meeting service requirements, with Phase 2 detailing protocols for implementing that architecture.
During preparation, it was decided to split Phase 1 into two parts. In December 2017, standardization of the non-autonomous, or Non-Standalone, architecture for 5G New Radio (NR) was completed. This first official set of 5G standards defines the wireless air interface for interworking with existing LTE base networks. This has allowed operators to combine 4G LTE networks with 5G NR, improving the latency and bandwidth of user data transmission.
In July 2018, the first stage of standardization for 5G Phase 1 was completed. As part of 3GPP Release 15, NR Standalone architecture specifications were released, indicating how the proposed 5G radio network will work with a 5G network core. In addition to radio network standardization, work was also done in 3GPP Release 15 to define the structure of most of the 5G network core.
Phase 2 of standardization of the 5G network core structure and use cases is the priority for current work on 3GPP Release 16, which should be completed by December 2019.
Because the 5G network core is still being standardized, nobody has a full picture yet of 5G network security. However, the standards released so far allow us to make some early assessments. To understand the issues at play, it is worth first reviewing the key use cases contemplated by 5G standards.
5G promises to be the standard for communication between billions of devices. At the moment, these devices and associated services fall into three main 5G use cases:
Enhanced Mobile Broadband (eMBB)
Improved consumer experience, more connected devices, faster connection speeds, virtual and augmented reality
Ultra-Reliable and LowLatency Communications (URLLC)
E-health, transport & logistics, environmental monitoring, smart energy networks, smart agriculture, smart retail
Enhanced Mobile Broadband (eMBB)
eMBB is an evolution of existing wireless broadband access services, with an emphasis on greater speed for consumer needs.
Key network requirements: data transmission speed up to 20 Gbps and latency less than 7 ms.
High-speed Internet access
HD video streaming
AR and VR services
Support for large numbers of subscribers in a single location
Ultra-Reliable and Low-Latency Communications (URLLC)
Quick and consistent data transmission is attractive to manufacturing, transport, healthcare, and other industries. URLLC services have strict requirements regarding network reliability and quality, prioritizing low latency, reliability, and low probability of error.
Key network requirements: probability of error from 10–5 to 10–8 and latency less than 3 ms.
Telemedicine, including remote diagnostics and robotic surgery
Remote control of industrial processes
Massive Machine-Type Communications (mMTC)
mMTC takes the IoT to the next level by bringing an even larger number of devices into the fold. This use case centers on high reliability, low power consumption, and support for high device densities in a given area.
Key network requirements: density of up to 1 million devices per square kilometer and battery life of up to 10 years without recharging.
Smart City systems
Transport and logistics
Production and staff monitoring
Other scenarios with exceptionally high concentrations of IoT sensors
5G use cases are shown |in the following graphic3
Naturally, this description of 5G use cases is not exhaustive. Communication technologies are always put to use in novel and unexpected ways. This is why the 5G network architecture has been designed with the capacity to adapt to new use cases with divergent requirements.
Implementing 5G will leave no part of the network untouched. The growing number of connected devices, plus the different demands placed on services under each use case, require new technologies both in the radio network and in the network core.
5G networks require a wide band of frequencies. The main difficulty for operators was that available spectrum is very limited. Suitable bands were already allocated for other uses. Ultimately, 5G networks were assigned new millimeter-wave and centimeter-wave bands never used before for mobile communications. But the new frequency bands brought a new problem: short millimeter waves do not travel well through obstacles.
To compensate, a solution was devised with massive MIMO (Multiple Input Multiple Output) antennae comprised of hundreds of elements working in concert. Beamforming creates directional beams to efficiently serve individual subscribers. Each 5G network subscriber receives a spatially and temporally tailored signal from the base station antenna, which provides only the service needed by that particular subscriber. This technology allows using the base station more efficiently and increasing 5G radio bandwidth. And with multi-connectivity, user equipment can connect to multiple base stations simultaneously.
Networks must serve devices and applications with varying traffic profiles. As such, it is important to accommodate the needs of applications and allocate network resources based on these diverse requirements. The 5G network flexibly allocates its resources, based on rules defined in software, for optimal service. This flexibility is achieved with the help of software-defined networking and network function virtualization.
SDN abstracts the network control level from data transmission devices, allowing implementation in software.
Key principles of SDN:
Data transmission is separate from data management.
Unified software centralizes network management.
Physical network resources are virtualized.
The result for operators is consistent automated control of network parameters, which allows the following:
Centralized application of policies
Easy and quick configuration by managing at the level of networks, as opposed to network elements
Optimization of traffic (L2/L3) transmission thanks to a larger number of routing paths
Network function virtualization
With NFV, it is possible to mix and match network functions on the software level to create unique telecommunication services without making changes at the hardware level. So an operator could launch a new service without purchasing new equipment or having to verify compatibility with what is already installed. NFV underpins network slicing, which splits a single physical network into multiple virtual networks (slices) so that a particular device can access only certain services with certain parameters at the right time.
Each slice in the network is allocated its own resources, such as bandwidth and service quality. By design, all slices are isolated from each other. Errors or failures in one slice should not affect services in the other slices. Network slicing improves the efficiency of mobile networks and quality of service.