Last year, TNS published a series of blogs that examined the major advantages of 5G, what 5G roaming looks like and how service providers can now keep their networks and network slices secure thanks to 5G’s enhanced security authentication and authorization. Now that carriers have significantly advanced their implementations of consumer non-standalone 5G and are working on building their fully standalone 5G networks, let’s revisit the 5G security narrative to discuss the important role authentication plays in securing networks, especially when it comes to roaming.

When designing their 5G architectures, operators considered the security gaps that existed with 3G and 4G. The encryption key, device messaging and SIM card exposure vulnerabilities that plagued previous generations were accounted for when constructing 5G networks.

The impetus to address security for the next generation of wireless networks traces back to the Chaos Communication Congress event in 2014 where it was reported that three hackers were able to infiltrate networks and steal subscribers’ information knowing just their telephone numbers. After that incident, operators placed an increased emphasis on mobile security and prioritized validating messages. Fast forward to today, carriers recognize security threats have evolved and become more sophisticated, but that 5G does unlock opportunities to mitigate a significant amount of risk by keeping service providers informed on current threats, including location tracking, intercepting SMS and phone calls and Denial-of-Service (DoS) attacks targeted towards a whole network segment or an individual subscriber.

Still, here are some of the hot-button security concerns TNS has been monitoring as 5G’s deployment continues.


With 3G and 4G roaming, bad actors utilized bid-down SIM card vulnerability to track subscribers and intercept SMS and voicemail messages. While 5G has reduced the risk that comes with SIM card vulnerability, roaming issues remain abundant. Once subscribers go out of home networks and onto roaming networks, bad actors can pounce. Often, hackers will pose as legitimate network operators and send a message to home carriers asking for sensitive information. To ensure that both network and subscribers are safe, carriers should track subscriber data, garner intelligence of where the subscriber is and initiate exchanges between both home networks and roaming networks to ensure solid authentication practices are in place.

Intergenerational Security

While 5G has taken extra steps to be more secure than previous generations, 5G coverage is not ubiquitous. While roaming, more often than not, users are alternating between 3G, 4G and 5G networks, offering hackers a large exposure area to attack.

Intergenerational security offers a solution that extends across all generations of wireless networks and is the foundation for 5G security worldwide. By taking metadata from 3G and 4G networks and having holistic security offering for all messages, carriers can provide true 5G security as subscribers jump from network to network.

Private 5G Networks

Private 5G networks offer enterprises broader and stronger coverage than previous network generations, as well as more secure coverage. Private 5G is an autonomous network and self-contained entity that can operate in itself and authentication is key to keeping organizations secure and private. For example, in factory automation, private 5G enables the responsiveness and low latency needed to minimize disruptions in manufacturing plans. Shortcomings often experienced in 3G and 4G networks, such as location tracking, SMS and voicemail interception, banking and financial hacks, DoS attacks and fraud attacks that result in revenue recognition issues like prepaid subscriber masking and international call masking are less of an issue on private 5G.

TNS has observed how 5G architecture has brought together IT and network support groups thus ensuring security is enforced on multiple layers. Because of this all-hands-on-deck approach, 5G is a unique opportunity for the telecom industry to take network, service and device security to levels not previously possible.

Ramesh Chellamani is Director of Product Management, Network Services at TNS with specific responsibility for the network services solutions within TNS’ Communications Market business.