TETRA and Private 5G: Better Together—for the Time Being

TETRA, which stands for Terrestrial Trunked Radio, is a digital radio communication standard primarily used for critical communication and Professional Mobile Radio (PMR) systems. In July 2023, employees of Dutch security firm Midnight Blue discovered important security vulnerabilities affecting all TETRA networks. These vulnerabilities—some of these characterized as being more critical than others—potentially allow an attacker to decrypt communications to inject messages, to deanonymize users, or to set the session key to zero for uplink interception. Seeing that TETRA networks are primarily used for highly critical communication like first responder networks, these vulnerabilities weigh even heavier.

At the same time, however, current users of TETRA networks are reluctant to replace the communication technology altogether. Just in October 2023, the Danish government, for example, decided to extend the nationwide TETRA network for first responder use cases. The reluctance might seem counterintuitive at first. Bearing in mind the use case and the resulting demands toward a new connectivity technology, however, underlines how costly and resource-intensive a reliable upgrade strategy can be.

The Danish Government is far from being the only entity that continues to rely on TETRA. It is interesting to see, however, that private cellular connectivity increasingly becomes part of the critical communication discussion as well. Earlier in 2023, NTT announced it would partner with Nippon Airport Radio Services to interconnect the operator’s 5G service with the wireless infrastructure and devices running on TETRA Narita International Airport (in Japan). In addition, ABI Research has knowledge about a few airports and oil & gas companies around the world looking at a similar level of integration. All these developments underline key decision-forming factors that are common to enterprises across different verticals when deciding about deploying new technology.

First, they are almost entirely pain-point focused. As enterprises have a range of heterogenous use cases to address (ranging from highly critical to not at all), different technologies will be best positioned to address them: In many of the applications where high bandwidth rate or low latency is important, 5G has an edge. However, for certain applications like underground mines where voice communication is critical and Line of Sight (LoS) is difficult to obtain, TETRA has an edge.

Second, enterprises place a high emphasis on existing digitization partners and established connectivity technologies. This is particularly important for highly critical use cases, where implementers need to be certain about the functionality of the underlying connectivity technology. Consequently, this applies to all highly critical use cases that TETRA communication currently targets.

ABI Research expects the transition from TETRA to alternative wireless communication technologies for especially critical applications to take place in several phases, particularly for private enterprise deployments that use TETRA for mission-critical communication within their enterprise premises (i.e., airports, logistics operators, or the military). As these enterprises have invested considerable amounts of capital into TETRA devices, they are—understandably—reluctant to rip and replace the entire infrastructure at once. To drive the adoption of private cellular connectivity, the telco industry will therefore need to develop private cellular solutions that allow enterprises to continue operating their TETRA device, while also enjoying the benefits of private cellular connectivity. First, vendors have reacted to the trend already (HMF’s 5G Smart Box, for example, supports TETRA devices on a private cellular network), but more vendors should embrace this opportunity to make the transition toward private cellular as easy as possible for enterprises. Planning this interoperability will span several different domains.

1. Establishing Interoperability Standards: First, the telco industry should exert all efforts to develop and establish standardized interfaces for ensuring seamless communication and coexistence between different technologies. This will allow both cellular network and dedicated TETRA vendors to both work on interoperable solutions from two different angles, thereby combining instead of duplicating efforts.
2. Gateway Solutions: Gateway solutions act as intermediaries that facilitate communication between different networks, protocols, or technologies. In the context of 5G and TETRA coexistence, a gateway can bridge the gap between these two distinct communication systems.
3. Security Measures: Vendors should implement robust security measures for both TETRA and private 5G networks. Security is critical, especially in sectors where TETRA is commonly used for mission-critical communications. Ensure that coexistence does not compromise the security of either network.

At the same time, service providers and system integrators will need to make sure they understand both their customer needs and the technology specifications to guide them through this transition period.

1. Develop Customized Solutions: Tailor service offerings to meet the specific needs of different industries and use cases. Offer customized solutions that leverage the strengths of both TETRA and 5G, ensuring a seamless transition for clients with diverse communication requirements. In this context, service providers need to bear in mind that aspects around network integrity and data sovereignty are particularly important to highly-critical deployments. Therefore, any solution will need to reconcile the need to secure data, particularly when using any public cellular network infrastructure.
2. Advance the Service Portfolio: Service providers should develop a diverse service portfolio catering to the needs of various industries. This might include public safety solutions, Industrial Internet of Things (IIoT) applications, and mission-critical communication services. In addition, service providers should offer support for dual-mode devices that can operate in both TETRA and 5G environments, allowing clients to transition gradually and ensuring backward compatibility.
3. Provide Security Assurances and Service Level Agreements (SLAs): Since TETRA targets particularly critical communication use cases, service providers will need to implement robust security measures for both TETRA and 5G networks. Consequently, any offering in that domain will have to target stringent security demands and will have to guarantee that TETRA traffic is separated from mobile network traffic; SLAs can assist with providing security and support services in this context.